CVE-2026-59846

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.

Affected Software

VendorProductVersion RangeStatus
Red HatRed Hat Enterprise Linux 100:0.12.0-3.el10_2 < *unaffected
Red HatRed Hat Enterprise Linux 80:0.9.6-17.el8_10 < *unaffected
Red HatRed Hat Enterprise Linux 80:0.9.6-17.el8_10 < *unaffected
Red HatRed Hat Enterprise Linux 90:0.10.4-19.el9_8 < *unaffected
Red HatRed Hat Enterprise Linux 90:0.10.4-19.el9_8 < *unaffected
Red HatRed Hat Hardened Images0.12.1-4.hum1 < *unaffected

Weaknesses

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

Workarounds

Make sure you are not executing connections with untrusted username inputs.

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References