Vulnerability-Lookup

rlsa-2026:27862

Vulnerability from osv_rocky

Published

2026-06-24 12:03

Modified

2026-07-08 12:08

Summary

Important: memcached security update

Details

memcached is a high-performance, distributed memory object caching system, generic in nature, but intended for use in speeding up dynamic web applications by alleviating database load.

Security Fix(es):

memcached: memcached: Username enumeration via timing side channel (CVE-2026-47783)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Severity

8.1 (High)


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

Credits

Rocky Enterprise Software Foundation

Red Hat

References

URL

Type

	https://errata.rockylinux.org/RLSA-2026:27862	ADVISORY
	https://bugzilla.redhat.com/show_bug.cgi?id=2480089	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Rocky Linux:9",
        "name": "memcached",
        "purl": "pkg:rpm/rocky-linux/memcached?distro=rocky-linux-9\u0026epoch=0"
      },
      "ranges": [
        {
          "database_specific": {
            "yum_repository": "AppStream"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0:1.6.9-7.el9_8.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "credits": [
    {
      "name": "Rocky Enterprise Software Foundation"
    },
    {
      "name": "Red Hat"
    }
  ],
  "details": "memcached is a high-performance, distributed memory object caching system, generic in nature, but intended for use in speeding up dynamic web applications by alleviating database load. \n\nSecurity Fix(es):\n\n* memcached: memcached: Username enumeration via timing side channel (CVE-2026-47783)\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.",
  "id": "RLSA-2026:27862",
  "modified": "2026-07-08T12:08:23.127090Z",
  "published": "2026-06-24T12:03:26.635873Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://errata.rockylinux.org/RLSA-2026:27862"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2480089"
    }
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Important: memcached security update",
  "upstream": [
    "CVE-2026-47783"
  ]
}

CVE-2026-47783 (GCVE-0-2026-47783)

Vulnerability from cvelistv5 – Published: 2026-05-20 05:43 – Updated: 2026-07-15 00:48

Summary

In memcached before 1.6.42, username data for SASL password database authentication has a timing side channel because a loop exits as soon as a valid username is found by sasl_server_userdb_checkpass.

Severity

8.1 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator (v2.0.3)

CWE

CWE-208 - Observable Timing Discrepancy

Assigner

mitre

References

8 references

URL	Tags
https://github.com/memcached/memcached/commit/d13…
https://github.com/memcached/memcached/compare/1.…
https://github.com/memcached/memcached/wiki/Relea…
https://access.redhat.com/security/cve/CVE-2026-47783	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2480089	issue-trackingx_refsource_REDHAT
https://security.access.redhat.com/data/csaf/v2/v…	x_sadp-csaf-vex
https://access.redhat.com/errata/RHSA-2026:27842	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:27862	vendor-advisoryx_refsource_REDHAT

Impacted products

6 products

Vendor	Product	Version
memcached	memcached	Affected: 0 , < 1.6.42 (semver)
Red Hat	Red Hat Enterprise Linux 10	Unaffected: 0:1.6.23-7.el10_2.1 , < * (rpm) cpe:/o:redhat:enterprise_linux:10.2
Red Hat	Red Hat Enterprise Linux 9	Unaffected: 0:1.6.9-7.el9_8.1 , < * (rpm) cpe:/a:redhat:enterprise_linux:9
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

Show details on NVD website

JSON

To clipboard

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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.

Action not permitted

rlsa-2026:27862

Vulnerability from osv_rocky

CVE-2026-47783 (GCVE-0-2026-47783)

Tags

Sightings

Nomenclature