Description
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.
Affected products
libssh: libssh; redhat: enterprise linux
References5
- access.redhat.com/errata/RHSA-2026:18160
- access.redhat.com/errata/RHSA-2026:18683
- access.redhat.com/security/cve/CVE-2026-0967 Third Party Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2436981 Third Party Advisory
- www.libssh.org/2026/02/10/libssh-0-12-0-and-0-11-4-security-rel… Release Notes
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 15 · as of 12 November 2026
- CWE
- CWE-1333
Could this be exploited in your environment?
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