CVE-2026-0966

A flaw was found in libssh. The API function `ssh_get_hexa()` is vulnerable to a denial of service when processing zero-length input. This can be exploited remotely by an attacker during GSSAPI (Generic Security Service Application Program Interface) authentication if the server's logging verbosity is set to `SSH_LOG_PACKET (3)` or higher. Successful exploitation could lead to a self-Denial of Service of the per-connection daemon process.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:18160
https://access.redhat.com/errata/RHSA-2026:18683
https://access.redhat.com/errata/RHSA-2026:7067	Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-0966	Mitigation Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2433121	Issue Tracking Vendor Advisory
https://www.libssh.org/2026/02/10/libssh-0-12-0-and-0-11-4-security-releases/	Release Notes

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:libssh:libssh::::::::
	cpe:2.3:a:redhat:hardened_images:-:::::::*
	cpe:2.3:a:redhat:openshift_container_platform:4.0:::::::*
	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 : 2026-03-26 21:17

Updated : 2026-09-01 12:17

NVD link : CVE-2026-0966

Mitre link : CVE-2026-0966

CVE.ORG link : CVE-2026-0966

JSON object : View

Products Affected

redhat

enterprise_linux
openshift_container_platform
hardened_images

libssh

libssh

CWE

CWE-124

Buffer Underwrite ('Buffer Underflow')

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The API function `ssh_get_hexa()` is vulnerable to a denial of service when processing zero-length input. This can be exploited remotely by an attacker during GSSAPI (Generic Security Service Application Program Interface) authentication if the server's logging verbosity is set to `SSH_LOG_PACKET (3)` or higher. Successful exploitation could lead to a self-Denial of Service of the per-connection daemon process."}, {"lang": "es", "value": "La funci\u00f3n API 'ssh_get_hexa()' es vulnerable cuando se proporciona una entrada de longitud 0 a esta funci\u00f3n. Esta funci\u00f3n se utiliza internamente en 'ssh_get_fingerprint_hash()' y 'ssh_print_hexa()' (obsoleta), la cual es vulnerable a la misma entrada (la longitud es proporcionada por la aplicaci\u00f3n que realiza la llamada).\n\nLa funci\u00f3n tambi\u00e9n se utiliza internamente en el c\u00f3digo gssapi para registrar los OID recibidos por el servidor durante la autenticaci\u00f3n GSSAPI. Esto podr\u00eda activarse de forma remota cuando el servidor permite la autenticaci\u00f3n GSSAPI y la verbosidad del registro se establece al menos en SSH_LOG_PACKET (3). Esto podr\u00eda causar un auto-DoS del proceso demonio por conexi\u00f3n."}], "lastModified": "2026-09-01T12:17:33.740", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:libssh:libssh:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "68C64024-6979-46E1-A57F-5C0228DC8DAD", "versionEndExcluding": "0.11.4"}, {"criteria": "cpe:2.3:a:redhat:hardened_images:-:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "87DEB507-5B64-47D7-9A50-3B87FD1E571F"}, {"criteria": "cpe:2.3:a:redhat:openshift_container_platform:4.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "932D137F-528B-4526-9A89-CD59FA1AB0FE"}, {"criteria": "cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F4CFF558-3C47-480D-A2F0-BABF26042943"}, {"criteria": "cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7F6FB57C-2BC7-487C-96DD-132683AEB35D"}, {"criteria": "cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D65C2163-CFC2-4ABB-8F4E-CB09CEBD006C"}], "operator": "OR"}]}], "sourceIdentifier": "secalert@redhat.com"}