CVE-2026-55654

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.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:36759
https://access.redhat.com/errata/RHSA-2026:47756
https://access.redhat.com/errata/RHSA-2026:47757
https://access.redhat.com/errata/RHSA-2026:54387
https://access.redhat.com/errata/RHSA-2026:58981
https://access.redhat.com/security/cve/CVE-2026-55654	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2462493	Exploit Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:openbsd:openssh:-:::::::*
	cpe:2.3:a:redhat:hardened_images:-:::::::*
	cpe:2.3:o:redhat:enterprise_linux:6.0:::::::*
	cpe:2.3:o:redhat:enterprise_linux:7.0:::::::*
	cpe:2.3:o:redhat:enterprise_linux:8.0:::::::*
	cpe:2.3:o:redhat:enterprise_linux:9.0:::::::*
	cpe:2.3:o:redhat:enterprise_linux:10.0:::::::*

History

No history.

Information

Published : 2026-06-23 04:17

Updated : 2026-09-01 09:16

NVD link : CVE-2026-55654

Mitre link : CVE-2026-55654

CVE.ORG link : CVE-2026-55654

JSON object : View

Products Affected

redhat

enterprise_linux
hardened_images

openbsd

openssh

CWE

CWE-125

Out-of-bounds Read

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