CVE-2026-44713 — pam_usb: Command injection via $TMUX environment variable leads to RCE as root

CVE-2026-44713

pam_usb: Command injection via $TMUX environment variable leads to RCE as root PUBLISHED

Description (CNA)

pam_usb provides hardware authentication for Linux using ordinary removable media. Prior to 0.8.7, src/tmux.c reads the user's $TMUX environment variable, splits it on commas, and interpolates the socket-path component directly into a shell command passed to popen(). Because the value is placed inside double-quotes without sanitisation, any value containing " terminates the quoted string and injects arbitrary shell syntax. popen() runs as root inside the PAM stack. This vulnerability is fixed in 0.8.7.

Affected (CNA)

Vendor / product	Versions
mcdope / pam_usb	affected < 0.8.7

CWE

CWE-78, CWE-116

References

https://github.com/mcdope/pam_usb/security/advisories/GHSA-822m-whrh-vrj8

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.