CVE-2026-59846

Libssh: libssh: information disclosure via proxycommand %r username expansion

State: Published
Severity: 3.9 Low
Published: Jul 21, 2026
Updated: Sep 1, 2026
Reserved: Jul 7, 2026

Description

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.

Scores

CVSS	Score	Vector	Source
3.1	3.9 Low	CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N	redhat

Weaknesses

CWE-78 Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
CWE-77 Improper Neutralization of Special Elements used in a Command ('Command Injection')

Affected Products

Product	Versions
Red Hat Enterprise Linux 10Red Hat	0:0.12.0-3.el10_2 and laterNot affected
Red Hat Enterprise Linux 8Red Hat	0:0.9.6-17.el8_10 and laterNot affected
Red Hat Enterprise Linux 8Red Hat	0:0.9.6-17.el8_10 and laterNot affected
Red Hat Enterprise Linux 9Red Hat	0:0.10.4-19.el9_8 and laterNot affected
Red Hat Enterprise Linux 9Red Hat	0:0.10.4-19.el9_8 and laterNot affected
Red Hat Hardened ImagesRed Hat	0.12.1-4.hum1 and laterNot affected

References

RHSA-2026:42922vendor-advisory
RHSA-2026:55855vendor-advisory
RHSA-2026:62217vendor-advisory
RHSA-2026:62218vendor-advisory
https://access.redhat.com/security/cve/CVE-2026-59846vdb-entry
RHBZ#2498179issue-tracking

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.