VulnerabilityDeferred

CVE-2026-44713

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.

HIGH 8.8EPSS 0.16%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.16%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 3.1: 8.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
EPSS: 0.16% probability · 5th percentile
CISA KEV: Not listed
Weakness: CWE-78, CWE-116
Source: security-advisories@github.com

References

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

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.