CVE-2026-18355 (GCVE-0-2026-18355)
Vulnerability from cvelistv5 – Published: 2026-09-07 14:14 – Updated: 2026-10-08 14:14
VLAI
EPSS
VEX
Title
389-ds-base: 389-ds-base: heap buffer overflow via sasl wrapped-record length lower-bound underflow in sasl_io_start_packet()
Summary
A heap buffer overflow flaw was found in the SASL I/O layer of 389 Directory Server (389-ds-base). In sasl_io_start_packet(), the wrapped-record length read from the wire is validated only against an upper bound. A small wire length (0, 1, or 2) produces an encrypted_buffer_count below the already-consumed encrypted_buffer_offset, causing an unsigned subtraction underflow in sasl_io_read_packet(). PR_Recv is then requested to read approximately 4 GiB into a 1024-byte heap buffer, resulting in a heap buffer overflow with attacker-controlled content. After a successful SASL bind with integrity protection (SSF > 0), a remote authenticated attacker can cause a denial of service or potentially achieve remote code execution. This flaw is distinct from CVE-2026-11774, whose fix only guards against upper-bound overflow.
Severity
7.5 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 16:40 UTC
CWE
- CWE-191 - Integer Underflow (Wrap or Wraparound)
Assigner
References
19 references
Impacted products
23 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Red Hat | Red Hat Directory Server 11.5 E4S for RHEL 8 |
Unaffected:
8060020260908152739.0ca98e7e , < *
(rpm)
cpe:/a:redhat:directory_server_e4s:11.5::el8 |
||
| Red Hat | Red Hat Directory Server 11.7 E4S for RHEL 8 |
Unaffected:
8080020260903102346.f969626e , < *
(rpm)
cpe:/a:redhat:directory_server_e4s:11.7::el8 |
||
| Red Hat | Red Hat Directory Server 11.9 for RHEL 8 |
Unaffected:
8100020260904171440.37ed7c03 , < *
(rpm)
cpe:/a:redhat:directory_server:11.9::el8 |
||
| Red Hat | Red Hat Directory Server 12.2 E4S for RHEL 9 |
Unaffected:
9020020260903155914.1674d574 , < *
(rpm)
cpe:/a:redhat:directory_server_e4s:12.2::el9 |
||
| Red Hat | Red Hat Directory Server 12.4 E4S for RHEL 9 |
Unaffected:
9040020260903102623.1674d574 , < *
(rpm)
cpe:/a:redhat:directory_server_e4s:12.4::el9 |
||
| Red Hat | Red Hat Enterprise Linux 10 |
Unaffected:
0:3.2.0-10.el10_2 , < *
(rpm)
cpe:/o:redhat:enterprise_linux:10.2 |
||
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support |
Unaffected:
0:3.0.6-21.el10_0 , < *
(rpm)
cpe:/o:redhat:enterprise_linux_eus:10.0 |
||
| Red Hat | Red Hat Enterprise Linux 7 Extended Lifecycle Support |
Unaffected:
0:1.3.11.1-15.el7_9 , < *
(rpm)
cpe:/o:redhat:rhel_els:7 |
||
| Red Hat | Red Hat Enterprise Linux 8 |
Unaffected:
8100020260904155442.25e700aa , < *
(rpm)
cpe:/a:redhat:enterprise_linux:8::appstream |
||
| Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support |
Unaffected:
8040020260901171549.96015a92 , < *
(rpm)
cpe:/a:redhat:rhel_aus:8.4::appstream cpe:/a:redhat:rhel_eus_long_life:8.4::appstream |
||
| Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On |
Unaffected:
8040020260901171549.96015a92 , < *
(rpm)
cpe:/a:redhat:rhel_aus:8.4::appstream cpe:/a:redhat:rhel_eus_long_life:8.4::appstream |
||
| Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support |
Unaffected:
8060020260901145727.824efc52 , < *
(rpm)
cpe:/a:redhat:rhel_aus:8.6::appstream cpe:/a:redhat:rhel_eus_long_life:8.6::appstream |
||
| Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On |
Unaffected:
8060020260901145727.824efc52 , < *
(rpm)
cpe:/a:redhat:rhel_aus:8.6::appstream cpe:/a:redhat:rhel_eus_long_life:8.6::appstream |
||
| Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service |
Unaffected:
8080020260831180218.6dbb3803 , < *
(rpm)
cpe:/a:redhat:rhel_e4s:8.8::appstream cpe:/a:redhat:rhel_tus:8.8::appstream |
||
| Red Hat | Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions |
Unaffected:
8080020260831180218.6dbb3803 , < *
(rpm)
cpe:/a:redhat:rhel_e4s:8.8::appstream cpe:/a:redhat:rhel_tus:8.8::appstream |
||
| Red Hat | Red Hat Enterprise Linux 9 |
Unaffected:
0:2.8.0-10.el9_8 , < *
(rpm)
cpe:/a:redhat:enterprise_linux:9::appstream cpe:/a:redhat:enterprise_linux:9::crb |
||
| Red Hat | Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions |
Unaffected:
0:2.2.4-22.el9_2 , < *
(rpm)
cpe:/a:redhat:rhel_e4s:9.2::appstream |
||
| Red Hat | Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions |
Unaffected:
0:2.4.5-29.el9_4 , < *
(rpm)
cpe:/a:redhat:rhel_e4s:9.4::appstream |
||
| Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support |
Unaffected:
0:2.6.1-24.el9_6 , < *
(rpm)
cpe:/a:redhat:rhel_eus:9.6::appstream cpe:/a:redhat:rhel_eus:9.6::crb |
||
| Red Hat | Red Hat Directory Server 13.2 |
Unaffected:
1788851765 , < *
(rpm)
cpe:/a:redhat:directory_server:13.2::el10 |
||
| Red Hat | Red Hat Directory Server 12 |
cpe:/a:redhat:directory_server:12
|
||
| Red Hat | Red Hat Directory Server 13 |
cpe:/a:redhat:directory_server:13
|
||
| Red Hat | Red Hat Enterprise Linux 6 |
cpe:/o:redhat:enterprise_linux:6
|
Date Public
2026-09-07 09:00
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-18355",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-09-08T16:40:59.242163Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-09-08T16:54:53.347Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server_e4s:11.5::el8"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:11",
"product": "Red Hat Directory Server 11.5 E4S for RHEL 8",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8060020260908152739.0ca98e7e",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server_e4s:11.7::el8"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:11",
"product": "Red Hat Directory Server 11.7 E4S for RHEL 8",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8080020260903102346.f969626e",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server:11.9::el8"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:11",
"product": "Red Hat Directory Server 11.9 for RHEL 8",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8100020260904171440.37ed7c03",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server_e4s:12.2::el9"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:12",
"product": "Red Hat Directory Server 12.2 E4S for RHEL 9",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "9020020260903155914.1674d574",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server_e4s:12.4::el9"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:12",
"product": "Red Hat Directory Server 12.4 E4S for RHEL 9",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "9040020260903102623.1674d574",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:10.2"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 10",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:3.2.0-10.el10_2",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux_eus:10.0"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 10.0 Extended Update Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:3.0.6-21.el10_0",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:rhel_els:7"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 7 Extended Lifecycle Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:1.3.11.1-15.el7_9",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:enterprise_linux:8::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8100020260904155442.25e700aa",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_aus:8.4::appstream",
"cpe:/a:redhat:rhel_eus_long_life:8.4::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8040020260901171549.96015a92",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_aus:8.4::appstream",
"cpe:/a:redhat:rhel_eus_long_life:8.4::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8040020260901171549.96015a92",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_aus:8.6::appstream",
"cpe:/a:redhat:rhel_eus_long_life:8.6::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8060020260901145727.824efc52",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_aus:8.6::appstream",
"cpe:/a:redhat:rhel_eus_long_life:8.6::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8060020260901145727.824efc52",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_e4s:8.8::appstream",
"cpe:/a:redhat:rhel_tus:8.8::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.8 Telecommunications Update Service",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8080020260831180218.6dbb3803",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_e4s:8.8::appstream",
"cpe:/a:redhat:rhel_tus:8.8::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8080020260831180218.6dbb3803",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:enterprise_linux:9::appstream",
"cpe:/a:redhat:enterprise_linux:9::crb"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 9",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:2.8.0-10.el9_8",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_e4s:9.2::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:2.2.4-22.el9_2",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_e4s:9.4::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:2.4.5-29.el9_4",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_eus:9.6::appstream",
"cpe:/a:redhat:rhel_eus:9.6::crb"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 9.6 Extended Update Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:2.6.1-24.el9_6",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://catalog.redhat.com/software/containers/",
"cpes": [
"cpe:/a:redhat:directory_server:13.2::el10"
],
"defaultStatus": "affected",
"packageName": "dirsrv/dirsrv-container-rhel10",
"product": "Red Hat Directory Server 13.2",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "1788851765",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server:12"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:12/389-ds-base",
"product": "Red Hat Directory Server 12",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server:13"
],
"defaultStatus": "unaffected",
"packageName": "389-ds-base",
"product": "Red Hat Directory Server 13",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:6"
],
"defaultStatus": "unaffected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 6",
"vendor": "Red Hat"
}
],
"credits": [
{
"lang": "en",
"value": "Red Hat would like to thank Adam Korczynski (Ada Logics), Arthur Chan (Ada Logics), David Korczynski (Ada Logics), and Team (Anthropic) for reporting this issue."
}
],
"datePublic": "2026-09-07T09:00:00.000Z",
"descriptions": [
{
"lang": "en",
"value": "A heap buffer overflow flaw was found in the SASL I/O layer of 389 Directory Server (389-ds-base). In sasl_io_start_packet(), the wrapped-record length read from the wire is validated only against an upper bound. A small wire length (0, 1, or 2) produces an encrypted_buffer_count below the already-consumed encrypted_buffer_offset, causing an unsigned subtraction underflow in sasl_io_read_packet(). PR_Recv is then requested to read approximately 4 GiB into a 1024-byte heap buffer, resulting in a heap buffer overflow with attacker-controlled content. After a successful SASL bind with integrity protection (SSF \u003e 0), a remote authenticated attacker can cause a denial of service or potentially achieve remote code execution. This flaw is distinct from CVE-2026-11774, whose fix only guards against upper-bound overflow."
}
],
"metrics": [
{
"other": {
"content": {
"namespace": "https://access.redhat.com/security/updates/classification/",
"value": "Important"
},
"type": "Red Hat severity rating"
}
},
{
"cvssV3_1": {
"attackComplexity": "HIGH",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 7.5,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"format": "CVSS"
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-191",
"description": "Integer Underflow (Wrap or Wraparound)",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-10-08T14:14:49.831Z",
"orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
"shortName": "redhat"
},
"references": [
{
"name": "RHSA-2026:64771",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64771"
},
{
"name": "RHSA-2026:64776",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64776"
},
{
"name": "RHSA-2026:64778",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64778"
},
{
"name": "RHSA-2026:64779",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64779"
},
{
"name": "RHSA-2026:64780",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64780"
},
{
"name": "RHSA-2026:64781",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64781"
},
{
"name": "RHSA-2026:64783",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64783"
},
{
"name": "RHSA-2026:64784",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64784"
},
{
"name": "RHSA-2026:64785",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64785"
},
{
"name": "RHSA-2026:64789",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64789"
},
{
"name": "RHSA-2026:64790",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64790"
},
{
"name": "RHSA-2026:64791",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64791"
},
{
"name": "RHSA-2026:64792",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64792"
},
{
"name": "RHSA-2026:64793",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64793"
},
{
"name": "RHSA-2026:64804",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64804"
},
{
"name": "RHSA-2026:65119",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:65119"
},
{
"name": "RHSA-2026:79217",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:79217"
},
{
"tags": [
"vdb-entry",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/security/cve/CVE-2026-18355"
},
{
"name": "RHBZ#2509186",
"tags": [
"issue-tracking",
"x_refsource_REDHAT"
],
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2509186"
}
],
"timeline": [
{
"lang": "en",
"time": "2026-07-08T00:00:00.000Z",
"value": "Reported to Red Hat."
},
{
"lang": "en",
"time": "2026-09-07T09:00:00.000Z",
"value": "Made public."
}
],
"title": "389-ds-base: 389-ds-base: heap buffer overflow via sasl wrapped-record length lower-bound underflow in sasl_io_start_packet()",
"workarounds": [
{
"lang": "en",
"value": "Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update the affected package as soon as possible."
}
],
"x_generator": {
"engine": "cvelib 1.8.0"
},
"x_redhatCweChain": "CWE-191: Integer Underflow (Wrap or Wraparound)"
}
},
"cveMetadata": {
"assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
"assignerShortName": "redhat",
"cveId": "CVE-2026-18355",
"datePublished": "2026-09-07T14:14:43.759Z",
"dateReserved": "2026-07-30T07:37:32.170Z",
"dateUpdated": "2026-10-08T14:14:49.831Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-18355",
"date": "2026-10-20",
"epss": "0.00837",
"percentile": "0.57077"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server_e4s:11.5::el8"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:11",
"product": "Red Hat Directory Server 11.5 E4S for RHEL 8",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8060020260908152739.0ca98e7e",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server_e4s:11.7::el8"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:11",
"product": "Red Hat Directory Server 11.7 E4S for RHEL 8",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8080020260903102346.f969626e",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server:11.9::el8"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:11",
"product": "Red Hat Directory Server 11.9 for RHEL 8",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8100020260904171440.37ed7c03",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server_e4s:12.2::el9"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:12",
"product": "Red Hat Directory Server 12.2 E4S for RHEL 9",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "9020020260903155914.1674d574",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server_e4s:12.4::el9"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:12",
"product": "Red Hat Directory Server 12.4 E4S for RHEL 9",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "9040020260903102623.1674d574",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:10.2"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 10",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:3.2.0-10.el10_2",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux_eus:10.0"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 10.0 Extended Update Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:3.0.6-21.el10_0",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:rhel_els:7"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 7 Extended Lifecycle Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:1.3.11.1-15.el7_9",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:enterprise_linux:8::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8100020260904155442.25e700aa",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_aus:8.4::appstream",
"cpe:/a:redhat:rhel_eus_long_life:8.4::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8040020260901171549.96015a92",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_aus:8.4::appstream",
"cpe:/a:redhat:rhel_eus_long_life:8.4::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8040020260901171549.96015a92",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_aus:8.6::appstream",
"cpe:/a:redhat:rhel_eus_long_life:8.6::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8060020260901145727.824efc52",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_aus:8.6::appstream",
"cpe:/a:redhat:rhel_eus_long_life:8.6::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8060020260901145727.824efc52",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_e4s:8.8::appstream",
"cpe:/a:redhat:rhel_tus:8.8::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.8 Telecommunications Update Service",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8080020260831180218.6dbb3803",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_e4s:8.8::appstream",
"cpe:/a:redhat:rhel_tus:8.8::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8080020260831180218.6dbb3803",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:enterprise_linux:9::appstream",
"cpe:/a:redhat:enterprise_linux:9::crb"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 9",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:2.8.0-10.el9_8",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_e4s:9.2::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:2.2.4-22.el9_2",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_e4s:9.4::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:2.4.5-29.el9_4",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_eus:9.6::appstream",
"cpe:/a:redhat:rhel_eus:9.6::crb"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 9.6 Extended Update Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:2.6.1-24.el9_6",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://catalog.redhat.com/software/containers/",
"cpes": [
"cpe:/a:redhat:directory_server:13.2::el10"
],
"defaultStatus": "affected",
"packageName": "dirsrv/dirsrv-container-rhel10",
"product": "Red Hat Directory Server 13.2",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "1788851765",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server:12"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:12/389-ds-base",
"product": "Red Hat Directory Server 12",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server:13"
],
"defaultStatus": "unaffected",
"packageName": "389-ds-base",
"product": "Red Hat Directory Server 13",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:6"
],
"defaultStatus": "unaffected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 6",
"vendor": "Red Hat"
}
],
"source": "secalert@redhat.com"
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "A heap buffer overflow flaw was found in the SASL I/O layer of 389 Directory Server (389-ds-base). In sasl_io_start_packet(), the wrapped-record length read from the wire is validated only against an upper bound. A small wire length (0, 1, or 2) produces an encrypted_buffer_count below the already-consumed encrypted_buffer_offset, causing an unsigned subtraction underflow in sasl_io_read_packet(). PR_Recv is then requested to read approximately 4 GiB into a 1024-byte heap buffer, resulting in a heap buffer overflow with attacker-controlled content. After a successful SASL bind with integrity protection (SSF \u003e 0), a remote authenticated attacker can cause a denial of service or potentially achieve remote code execution. This flaw is distinct from CVE-2026-11774, whose fix only guards against upper-bound overflow."
}
],
"id": "CVE-2026-18355",
"lastModified": "2026-10-08T15:17:52.090",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "HIGH",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 7.5,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.6,
"impactScore": 5.9,
"source": "secalert@redhat.com",
"type": "Secondary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-18355",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-09-08T16:40:59.242163Z",
"version": "2.0.3"
}
}
]
},
"published": "2026-09-07T15:17:30.867",
"references": [
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:64771"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:64776"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:64778"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:64779"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:64780"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:64781"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:64783"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:64784"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:64785"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:64789"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:64790"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:64791"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:64792"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:64793"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:64804"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:65119"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/errata/RHSA-2026:79217"
},
{
"source": "secalert@redhat.com",
"url": "https://access.redhat.com/security/cve/CVE-2026-18355"
},
{
"source": "secalert@redhat.com",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2509186"
}
],
"sourceIdentifier": "secalert@redhat.com",
"vulnStatus": "Awaiting Analysis",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-191"
}
],
"source": "secalert@redhat.com",
"type": "Secondary"
}
]
}
},
"redhat_vex": {
"aggregate_severity": "Important",
"current_release_date": "2026-10-08T14:14:48+00:00",
"cve": "CVE-2026-18355",
"id": "CVE-2026-18355",
"initial_release_date": "2026-09-07T09:00:00+00:00",
"product_status:fixed": "486",
"product_status:known_affected": "1",
"product_status:known_not_affected": "5",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "389-ds-base: 389-ds-base: heap buffer overflow via SASL wrapped-record length lower-bound underflow in sasl_io_start_packet()",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-18355.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "important",
"current_release_date": "2026-10-09T00:21:38Z",
"cve": "CVE-2026-18355",
"id": "CVE-2026-18355",
"initial_release_date": "2026-09-09T00:26:22Z",
"product_status:known_affected": "116",
"product_status:recommended": "54",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2026-18355",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-18355.json",
"version": "5"
},
"vulnrichment": {
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-18355",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-09-08T16:40:59.242163Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-09-08T16:41:00.775Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server_e4s:11.5::el8"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:11",
"product": "Red Hat Directory Server 11.5 E4S for RHEL 8",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8060020260908152739.0ca98e7e",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server_e4s:11.7::el8"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:11",
"product": "Red Hat Directory Server 11.7 E4S for RHEL 8",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8080020260903102346.f969626e",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server:11.9::el8"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:11",
"product": "Red Hat Directory Server 11.9 for RHEL 8",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8100020260904171440.37ed7c03",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server_e4s:12.2::el9"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:12",
"product": "Red Hat Directory Server 12.2 E4S for RHEL 9",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "9020020260903155914.1674d574",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server_e4s:12.4::el9"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:12",
"product": "Red Hat Directory Server 12.4 E4S for RHEL 9",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "9040020260903102623.1674d574",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:10.2"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 10",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:3.2.0-10.el10_2",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux_eus:10.0"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 10.0 Extended Update Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:3.0.6-21.el10_0",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:rhel_els:7"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 7 Extended Lifecycle Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:1.3.11.1-15.el7_9",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:enterprise_linux:8::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8100020260904155442.25e700aa",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_aus:8.4::appstream",
"cpe:/a:redhat:rhel_eus_long_life:8.4::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8040020260901171549.96015a92",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_aus:8.4::appstream",
"cpe:/a:redhat:rhel_eus_long_life:8.4::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8040020260901171549.96015a92",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_aus:8.6::appstream",
"cpe:/a:redhat:rhel_eus_long_life:8.6::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8060020260901145727.824efc52",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_aus:8.6::appstream",
"cpe:/a:redhat:rhel_eus_long_life:8.6::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8060020260901145727.824efc52",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_e4s:8.8::appstream",
"cpe:/a:redhat:rhel_tus:8.8::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.8 Telecommunications Update Service",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8080020260831180218.6dbb3803",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_e4s:8.8::appstream",
"cpe:/a:redhat:rhel_tus:8.8::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds:1.4",
"product": "Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "8080020260831180218.6dbb3803",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:enterprise_linux:9::appstream",
"cpe:/a:redhat:enterprise_linux:9::crb"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 9",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:2.8.0-10.el9_8",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_e4s:9.2::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:2.2.4-22.el9_2",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_e4s:9.4::appstream"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:2.4.5-29.el9_4",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:rhel_eus:9.6::appstream",
"cpe:/a:redhat:rhel_eus:9.6::crb"
],
"defaultStatus": "affected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 9.6 Extended Update Support",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "0:2.6.1-24.el9_6",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://catalog.redhat.com/software/containers/",
"cpes": [
"cpe:/a:redhat:directory_server:13.2::el10"
],
"defaultStatus": "affected",
"packageName": "dirsrv/dirsrv-container-rhel10",
"product": "Red Hat Directory Server 13.2",
"vendor": "Red Hat",
"versions": [
{
"lessThan": "*",
"status": "unaffected",
"version": "1788851765",
"versionType": "rpm"
}
]
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server:12"
],
"defaultStatus": "affected",
"packageName": "redhat-ds:12/389-ds-base",
"product": "Red Hat Directory Server 12",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/a:redhat:directory_server:13"
],
"defaultStatus": "unaffected",
"packageName": "389-ds-base",
"product": "Red Hat Directory Server 13",
"vendor": "Red Hat"
},
{
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"cpes": [
"cpe:/o:redhat:enterprise_linux:6"
],
"defaultStatus": "unaffected",
"packageName": "389-ds-base",
"product": "Red Hat Enterprise Linux 6",
"vendor": "Red Hat"
}
],
"credits": [
{
"lang": "en",
"value": "Red Hat would like to thank Adam Korczynski (Ada Logics), Arthur Chan (Ada Logics), David Korczynski (Ada Logics), and Team (Anthropic) for reporting this issue."
}
],
"datePublic": "2026-09-07T09:00:00.000Z",
"descriptions": [
{
"lang": "en",
"value": "A heap buffer overflow flaw was found in the SASL I/O layer of 389 Directory Server (389-ds-base). In sasl_io_start_packet(), the wrapped-record length read from the wire is validated only against an upper bound. A small wire length (0, 1, or 2) produces an encrypted_buffer_count below the already-consumed encrypted_buffer_offset, causing an unsigned subtraction underflow in sasl_io_read_packet(). PR_Recv is then requested to read approximately 4 GiB into a 1024-byte heap buffer, resulting in a heap buffer overflow with attacker-controlled content. After a successful SASL bind with integrity protection (SSF \u003e 0), a remote authenticated attacker can cause a denial of service or potentially achieve remote code execution. This flaw is distinct from CVE-2026-11774, whose fix only guards against upper-bound overflow."
}
],
"metrics": [
{
"other": {
"content": {
"namespace": "https://access.redhat.com/security/updates/classification/",
"value": "Important"
},
"type": "Red Hat severity rating"
}
},
{
"cvssV3_1": {
"attackComplexity": "HIGH",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 7.5,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"format": "CVSS"
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-191",
"description": "Integer Underflow (Wrap or Wraparound)",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-10-08T14:14:49.831Z",
"orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
"shortName": "redhat"
},
"references": [
{
"name": "RHSA-2026:64771",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64771"
},
{
"name": "RHSA-2026:64776",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64776"
},
{
"name": "RHSA-2026:64778",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64778"
},
{
"name": "RHSA-2026:64779",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64779"
},
{
"name": "RHSA-2026:64780",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64780"
},
{
"name": "RHSA-2026:64781",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64781"
},
{
"name": "RHSA-2026:64783",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64783"
},
{
"name": "RHSA-2026:64784",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64784"
},
{
"name": "RHSA-2026:64785",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64785"
},
{
"name": "RHSA-2026:64789",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64789"
},
{
"name": "RHSA-2026:64790",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64790"
},
{
"name": "RHSA-2026:64791",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64791"
},
{
"name": "RHSA-2026:64792",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64792"
},
{
"name": "RHSA-2026:64793",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64793"
},
{
"name": "RHSA-2026:64804",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:64804"
},
{
"name": "RHSA-2026:65119",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:65119"
},
{
"name": "RHSA-2026:79217",
"tags": [
"vendor-advisory",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/errata/RHSA-2026:79217"
},
{
"tags": [
"vdb-entry",
"x_refsource_REDHAT"
],
"url": "https://access.redhat.com/security/cve/CVE-2026-18355"
},
{
"name": "RHBZ#2509186",
"tags": [
"issue-tracking",
"x_refsource_REDHAT"
],
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2509186"
}
],
"timeline": [
{
"lang": "en",
"time": "2026-07-08T00:00:00.000Z",
"value": "Reported to Red Hat."
},
{
"lang": "en",
"time": "2026-09-07T09:00:00.000Z",
"value": "Made public."
}
],
"title": "389-ds-base: 389-ds-base: heap buffer overflow via sasl wrapped-record length lower-bound underflow in sasl_io_start_packet()",
"workarounds": [
{
"lang": "en",
"value": "Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update the affected package as soon as possible."
}
],
"x_generator": {
"engine": "cvelib 1.8.0"
},
"x_redhatCweChain": "CWE-191: Integer Underflow (Wrap or Wraparound)"
}
},
"cveMetadata": {
"assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
"assignerShortName": "redhat",
"cveId": "CVE-2026-18355",
"datePublished": "2026-09-07T14:14:43.759Z",
"dateReserved": "2026-07-30T07:37:32.170Z",
"dateUpdated": "2026-10-08T14:14:49.831Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline
Sightings and recorded dates, grouped by day · UTC
Loading timeline…
Loading…
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.