Vulnerability-Lookup

ubuntu-cve-2026-18663

Vulnerability from osv_ubuntu

Published

2026-08-12 10:17

Modified

2026-08-19 11:01

Summary

Details

A flaw was found in 389-ds-base. The get_ldapmessage_controls_ext() function frees the parsed controls array on the Session Tracking critical-control rejection path without clearing the SLAPI_REQCONTROLS pblock slot. Operation teardown then frees the same pointer again, causing a double-free. An unauthenticated remote attacker can trigger this with a single BIND request carrying a critical Session Tracking control, resulting in heap corruption and potential denial of service.

Severity

5.9 (Medium)


                    
                      CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-18663	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-18663	REPORT
	https://bugzilla.redhat.com/show_bug.cgi?id=2510631	REPORT
	https://access.redhat.com/security/cve/CVE-2026-18663	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "389-ds",
            "binary_version": "1.3.4.9-1ubuntu0.1~esm1"
          },
          {
            "binary_name": "389-ds-base",
            "binary_version": "1.3.4.9-1ubuntu0.1~esm1"
          },
          {
            "binary_name": "389-ds-base-libs",
            "binary_version": "1.3.4.9-1ubuntu0.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "389-ds-base",
        "purl": "pkg:deb/ubuntu/389-ds-base@1.3.4.9-1ubuntu0.1~esm1?arch=source\u0026distro=esm-apps/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.3.12-1build1",
        "1.3.3.13-1",
        "1.3.4.5-2",
        "1.3.4.8-1",
        "1.3.4.8-3",
        "1.3.4.8-3ubuntu1",
        "1.3.4.8-4",
        "1.3.4.9-1",
        "1.3.4.9-1ubuntu0.1~esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "389-ds",
            "binary_version": "1.3.7.10-1ubuntu1+esm1"
          },
          {
            "binary_name": "389-ds-base",
            "binary_version": "1.3.7.10-1ubuntu1+esm1"
          },
          {
            "binary_name": "389-ds-base-libs",
            "binary_version": "1.3.7.10-1ubuntu1+esm1"
          },
          {
            "binary_name": "python3-dirsrvtests",
            "binary_version": "1.3.7.10-1ubuntu1+esm1"
          },
          {
            "binary_name": "python3-lib389",
            "binary_version": "1.3.7.10-1ubuntu1+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "389-ds-base",
        "purl": "pkg:deb/ubuntu/389-ds-base@1.3.7.10-1ubuntu1+esm1?arch=source\u0026distro=esm-apps/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.3.7.5-1",
        "1.3.7.5-1build1",
        "1.3.7.5-1build2",
        "1.3.7.9-1",
        "1.3.7.10-1",
        "1.3.7.10-1ubuntu1",
        "1.3.7.10-1ubuntu1+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "389-ds",
            "binary_version": "1.4.3.6-2ubuntu0.1~esm1"
          },
          {
            "binary_name": "389-ds-base",
            "binary_version": "1.4.3.6-2ubuntu0.1~esm1"
          },
          {
            "binary_name": "389-ds-base-libs",
            "binary_version": "1.4.3.6-2ubuntu0.1~esm1"
          },
          {
            "binary_name": "cockpit-389-ds",
            "binary_version": "1.4.3.6-2ubuntu0.1~esm1"
          },
          {
            "binary_name": "python3-lib389",
            "binary_version": "1.4.3.6-2ubuntu0.1~esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "389-ds-base",
        "purl": "pkg:deb/ubuntu/389-ds-base@1.4.3.6-2ubuntu0.1~esm1?arch=source\u0026distro=esm-apps/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.4.1.6-4",
        "1.4.1.6-4build1",
        "1.4.2.4-1",
        "1.4.2.4-1build1",
        "1.4.3.2-1",
        "1.4.3.2-1build1",
        "1.4.3.6-2",
        "1.4.3.6-2ubuntu0.1~esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "389-ds",
            "binary_version": "2.0.15-1ubuntu2"
          },
          {
            "binary_name": "389-ds-base",
            "binary_version": "2.0.15-1ubuntu2"
          },
          {
            "binary_name": "389-ds-base-libs",
            "binary_version": "2.0.15-1ubuntu2"
          },
          {
            "binary_name": "cockpit-389-ds",
            "binary_version": "2.0.15-1ubuntu2"
          },
          {
            "binary_name": "python3-lib389",
            "binary_version": "2.0.15-1ubuntu2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "389-ds-base",
        "purl": "pkg:deb/ubuntu/389-ds-base@2.0.15-1ubuntu2?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.4.4.11-2build1",
        "1.4.4.11-2build2",
        "1.4.4.17-1",
        "2.0.11-2",
        "2.0.14-1",
        "2.0.15-1",
        "2.0.15-1ubuntu2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "389-ds",
            "binary_version": "2.4.5+dfsg1-1"
          },
          {
            "binary_name": "389-ds-base",
            "binary_version": "2.4.5+dfsg1-1"
          },
          {
            "binary_name": "389-ds-base-libs",
            "binary_version": "2.4.5+dfsg1-1"
          },
          {
            "binary_name": "cockpit-389-ds",
            "binary_version": "2.4.5+dfsg1-1"
          },
          {
            "binary_name": "python3-lib389",
            "binary_version": "2.4.5+dfsg1-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "389-ds-base",
        "purl": "pkg:deb/ubuntu/389-ds-base@2.4.5+dfsg1-1?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2.3.4+dfsg1-1",
        "2.4.4+dfsg1-1ubuntu1",
        "2.4.4+dfsg1-1ubuntu4",
        "2.4.4+dfsg1-3",
        "2.4.5+dfsg1-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "389-ds",
            "binary_version": "3.1.2+vendor1-2"
          },
          {
            "binary_name": "389-ds-base",
            "binary_version": "3.1.2+vendor1-2"
          },
          {
            "binary_name": "389-ds-base-libs",
            "binary_version": "3.1.2+vendor1-2"
          },
          {
            "binary_name": "cockpit-389-ds",
            "binary_version": "3.1.2+vendor1-2"
          },
          {
            "binary_name": "python3-lib389",
            "binary_version": "3.1.2+vendor1-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "389-ds-base",
        "purl": "pkg:deb/ubuntu/389-ds-base@3.1.2+vendor1-2?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.1.2+dfsg1-1",
        "3.1.2+vendor1-2"
      ]
    }
  ],
  "aliases": [],
  "details": "A flaw was found in 389-ds-base. The get_ldapmessage_controls_ext() function frees the parsed controls array on the Session Tracking critical-control rejection path without clearing the SLAPI_REQCONTROLS pblock slot. Operation teardown then frees the same pointer again, causing a double-free. An unauthenticated remote attacker can trigger this with a single BIND request carrying a critical Session Tracking control, resulting in heap corruption and potential denial of service.",
  "id": "UBUNTU-CVE-2026-18663",
  "modified": "2026-08-19T11:01:27Z",
  "published": "2026-08-12T10:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-18663"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-18663"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2510631"
    },
    {
      "type": "REPORT",
      "url": "https://access.redhat.com/security/cve/CVE-2026-18663"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-18663"
  ]
}

CVE-2026-18663 (GCVE-0-2026-18663)

Vulnerability from cvelistv5 – Published: 2026-08-12 09:35 – Updated: 2026-08-13 15:41

Title

389-ds-base: 389-ds-base: pre-authentication double-free in get_ldapmessage_controls_ext() via critical session tracking control

Summary

Severity

5.9 (Medium)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-13 15:40 UTC

CWE

CWE-415 - Double Free

Assigner

redhat redhat root

References

2 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-18663	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2510631	issue-trackingx_refsource_REDHAT

Impacted products

8 products

Vendor	Product	Version
Red Hat	Red Hat Directory Server 11	cpe:/a:redhat:directory_server:11
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 10	cpe:/o:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 6	cpe:/o:redhat:enterprise_linux:6
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:enterprise_linux:7
Red Hat	Red Hat Enterprise Linux 8	cpe:/o:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 9	cpe:/o:redhat:enterprise_linux:9

Date Public

2026-08-12 07:21

Credits

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.

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-18663",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-13T15:40:56.481579Z",
                "version": "2.0.3"
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        "providerMetadata": {
          "dateUpdated": "2026-08-13T15:41:09.335Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
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    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:directory_server:11"
          ],
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          "packageName": "redhat-ds:11/389-ds-base",
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          "vendor": "Red Hat"
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          "cpes": [
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          "cpes": [
            "cpe:/o:redhat:enterprise_linux:8"
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          "defaultStatus": "unaffected",
          "packageName": "389-ds:1.4/389-ds-base",
          "product": "Red Hat Enterprise Linux 8",
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          ],
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          "lang": "en",
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      ],
      "title": "389-ds-base: 389-ds-base: pre-authentication double-free in get_ldapmessage_controls_ext() via critical session tracking control",
      "workarounds": [
        {
          "lang": "en",
          "value": "On builds that include upstream Issue 7389 (committed 2026-04-09, present in 389-ds-base-3.2 branch), administrators can add the Session Tracking control OID (1.3.6.1.4.1.21008.108.63.1) to the ds-ignored-control-criticality configuration attribute. This causes the server to ignore the criticality flag on this control, preventing the vulnerable rejection path from being reached.\n\nAdditionally, network-level restriction of access to the LDAP port (389/636) to trusted clients reduces exposure."
        }
      ],
      "x_generator": {
        "engine": "cvelib 1.8.0"
      },
      "x_redhatCweChain": "CWE-415: Double Free"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
    "assignerShortName": "redhat",
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    "datePublished": "2026-08-12T09:35:26.681Z",
    "dateReserved": "2026-08-03T13:22:45.359Z",
    "dateUpdated": "2026-08-13T15:41:09.335Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

Detection rules are retrieved from Rulezet.

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.

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.