Inefficient Regular Expression Complexity Affecting rhcos package, versions *


Severity

Recommended
0.0
low
0
10

Based on Red Hat Enterprise Linux security rating.

Threat Intelligence

EPSS
0.07% (21st percentile)

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  • Snyk IDSNYK-RHEL9-RHCOS-15471835
  • published12 Mar 2026
  • disclosed10 Feb 2026

Introduced: 10 Feb 2026

CVE-2026-0967  (opens in a new tab)
CWE-1333  (opens in a new tab)

How to fix?

There is no fixed version for RHEL:9 rhcos.

NVD Description

Note: Versions mentioned in the description apply only to the upstream rhcos package and not the rhcos package as distributed by RHEL. See How to fix? for RHEL:9 relevant fixed versions and status.

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 Base Scores

version 3.1