5.5Medium

Libssh Libssh

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.

What this means for your business

  • It affects Libssh. It matters if your company, or a supplier that handles your data, runs it.
  • An attacker can use it only with access to the machine itself, without a login, but only after tricking someone into an action such as opening a file or a link.

What to do

  1. 1Check whether your company or your suppliers run Libssh, and which version. The affected versions are listed further down this page.
  2. 2If you do, follow the vendor's guidance. No patch reference has been published yet.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

Scoring

CVSS
5.5 (v3.1)
Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Weakness
CWE-1333
Assigned by
secalert@redhat.com

Dates

Published
2026-03-26
Last modified
2026-09-01
Sources
NVD

Affected products

  • Libssh Libssh- 0.11.3
  • Redhat Enterprise Linux9.0, 10.0

As listed in the NVD configuration data. Not a statement about your estate.

References