Low [CVE-2026-59846] information disclosure via ProxyCommand %r username expansion
This low-severity Red Hat Linux advisory covers CVE-2026-59846 affecting Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9.
Aggregated and source-linked by VulniPulse. Data sources, validation and limitations.
VulniPulse record published Record updated
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Summary
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.
Red Hat severity: Low — CVSS 3.9 (CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N). Weakness: CWE-78.
Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9; Red Hat Hardened Images. Red Hat fixing advisory: RHSA-2026:55855, RHSA-2026:62218, RHSA-2026:62217, RHSA-2026:42922.
Affected products named by the advisory: Red Hat package: libssh.
Affected versions
No affected-version range was extracted from the source record. The vendor advisory is authoritative. Check it before change work.
Official advisory · high-confidence parse· fetched 8 days ago·verify at source
- libssh-0:0.12.0-3.el10_2
- libssh-0:0.9.6-17.el8_10
- libssh-0:0.10.4-19.el9_8
- libssh-main-0.12.1-4.hum1
- RHSA-2026:55855
- RHSA-2026:62218
- RHSA-2026:62217
- RHSA-2026:42922
Official advisory · high-confidence parse· fetched 8 days ago·verify at source
Mitigation checklist
- Make sure you are not executing connections with untrusted username inputs.
Official advisory · high-confidence parse· fetched 8 days ago·verify at source
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