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

Vulnerability from cvelistv5 – Published: 2026-06-23 03:37 – Updated: 2026-11-06 19:07
VLAI
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 · CISA-ADP (v2.0.3)
Decision recorded 2026-06-23 12:11 UTC
CWE
Assigner
redhat CNA under the redhat root
CNA scorecard B 82/100 over 1200 records in the last 180 days details
References
URL Tags
https://access.redhat.com/errata/RHSA-2026:36759 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:47756 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:47757 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:54387 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:58981 vendor-advisoryx_refsource_REDHAT
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
Vendor Product Version CPE status
Red Hat Red Hat Enterprise Linux 10 Unaffected: 0:9.9p1-25.el10_2 , < * (rpm)
    cpe:/o:redhat:enterprise_linux:10.2
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 9 Unaffected: 0:9.9p1-9.el9_8 , < * (rpm)
    cpe:/a:redhat:enterprise_linux:9::appstream
    cpe:/o:redhat:enterprise_linux:9::baseos
Create a notification for this product.
Red Hat Red Hat Hardened Images Unaffected: 10.3p1-6.hum1 , < * (rpm)
    cpe:/a:redhat:hummingbird:1
Create a notification for this product.
Red Hat Red Hat Update Infrastructure 5 Unaffected: 1786435483 , < * (rpm)
    cpe:/a:redhat:rhui:5::el9
Create a notification for this product.
Red Hat Red Hat Update Infrastructure 5 Unaffected: 1786533529 , < * (rpm)
    cpe:/a:redhat:rhui:5::el9
Create a notification for this product.
Red Hat Red Hat Update Infrastructure 5 Unaffected: 1787135742 , < * (rpm)
    cpe:/a:redhat:rhui:5::el9
Create a notification for this product.
Red Hat Red Hat Update Infrastructure 5 Unaffected: 1787241260 , < * (rpm)
    cpe:/a:redhat:rhui:5::el9
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 6     cpe:/o:redhat:rhel_els:6
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:rhel_els:7
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 8     cpe:/a:redhat:enterprise_linux:8
Create a notification for this product.
Red Hat Red Hat OpenShift Container Platform 4     cpe:/a:redhat:openshift:4
Create a notification for this product.
Red Hat Red Hat OpenShift Container Platform 5     cpe:/a:redhat:openshift:5
Create a notification for this product.
Date Public
2026-06-22 23:18
Credits
This issue was discovered by In partnership with Red Hat (Aisle.com).
Show details on NVD website
To clipboard 

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Sightings

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