RCE in Libssh

CVE-2026-59846

A flaw was found in libssh. A malicious username expanded through %r in ProxyCommand handling can inject shell metacharacters, exposing environment variables and causing unintended shell behavior.

Vulnerability class: Command Injection (OS Command Injection)

EPSS: 0.001 (2.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 3.9 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-59846?
CVE-2026-59846 is a low-severity vulnerability in Libssh, classified under OS Command Injection. CVSS score: 3.9/10. Published 2026-07-21.
How severe is CVE-2026-59846?
Low severity. CVSS v3 base score is 3.9 out of 10.