Vulnerability-Lookup

CVE-2026-55654 (GCVE-0-2026-55654)

Vulnerability from cvelistv5 – Published: 2026-06-23 03:37 – Updated: 2026-06-23 12:12

Title

Openssh: heap out-of-bounds read in red hat enterprise linux versions of openssh gssapi indicator cleanup due to missing null sentinel termination

Summary

A flaw was found in OpenSSH. This vulnerability, a heap out-of-bounds read, occurs during the cleanup of GSSAPI (Generic Security Service Application Programming Interface) indicators when a trailing NULL termination is missing in the auth-indicators array. A remote attacker, under specific configurations involving GSSAPI authentication and a Kerberos environment, could exploit this to cause the SSH authentication path to crash or abort. This leads to a denial of service (DoS), impacting the availability of the SSH service.

Severity

3.7 (Low)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-125 - Out-of-bounds Read

Assigner

redhat

References

2 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-55654	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2462493	issue-trackingx_refsource_REDHAT

Impacted products

7 products

Vendor	Product	Version
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
Red Hat	Red Hat Hardened Images	cpe:/a:redhat:hummingbird:1
Red Hat	Red Hat OpenShift Container Platform 4	cpe:/a:redhat:openshift:4

Date Public

2026-06-22 23:18

Show details on NVD website

JSON

To clipboard

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GHSA-5MX2-7G4J-9M39

Vulnerability from github – Published: 2026-06-23 06:30 – Updated: 2026-06-23 06:30

Details

Severity

3.7 (Low)


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

Show details on source website

JSON

To clipboard

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  "affected": [],
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    "CVE-2026-55654"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-125"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-23T04:17:40Z",
    "severity": "LOW"
  },
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  "id": "GHSA-5mx2-7g4j-9m39",
  "modified": "2026-06-23T06:30:41Z",
  "published": "2026-06-23T06:30:41Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-55654"
    },
    {
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      "type": "CVSS_V3"
    }
  ]
}

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.

Action not permitted

CVE-2026-55654 (GCVE-0-2026-55654)

GHSA-5MX2-7G4J-9M39

Tags

Sightings

Nomenclature