CVE-2026-0967

A flaw was found in libssh. A remote attacker, by controlling client configuration files or known_hosts files, could craft specific hostnames that when processed by the `match_pattern()` function can lead to inefficient regular expression backtracking. This can cause timeouts and resource exhaustion, resulting in a Denial of Service (DoS) for the client.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

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/security/cve/CVE-2026-0967	Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2436981	Third Party 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: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 13:18

NVD link : CVE-2026-0967

Mitre link : CVE-2026-0967

CVE.ORG link : CVE-2026-0967

JSON object : View

Products Affected

redhat

enterprise_linux

libssh

libssh

CWE

CWE-1333

Inefficient Regular Expression Complexity

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A remote attacker, by controlling client configuration files or known_hosts files, could craft specific hostnames that when processed by the `match_pattern()` function can lead to inefficient regular expression backtracking. This can cause timeouts and resource exhaustion, resulting in a Denial of Service (DoS) for the client."}, {"lang": "es", "value": "Se encontr\u00f3 una vulnerabilidad en libssh. Un atacante remoto, al controlar los archivos de configuraci\u00f3n del cliente o los archivos known_hosts, podr\u00eda crear nombres de host espec\u00edficos que, al ser procesados por la funci\u00f3n `match_pattern()`, pueden llevar a un retroceso ineficiente de expresiones regulares. Esto puede causar tiempos de espera y agotamiento de recursos, lo que resulta en una denegaci\u00f3n de servicio (DoS) para el cliente."}], "lastModified": "2026-09-01T13:18:06.947", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:libssh:libssh:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "2366D711-FD0B-4A04-92BA-DE6DA0ED1BCF", "versionEndIncluding": "0.11.3"}, {"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"}