CVE-2026-47274 pam_usb: Uncontrolled search path in pam_usb tools allows privilege escalation via PATH manipulation
Attackers can escalate privileges by manipulating the PATH environment variable to execute malicious binaries during PAM authentication in pam_usb.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-47274?
CVE-2026-47274 is a medium-severity vulnerability in mcdope pam_usb, published on 27 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
pam_usb provides hardware authentication for Linux using ordinary removable media. Prior to 0.9.0, multiple pam_usb helper tools resolved external binaries through the PATH environment variable rather than using absolute paths. An attacker who can influence the process environment during PAM authentication or tool execution could substitute malicious binaries. The affected tools are pamusb-check (src/tmux.c), pamusb-conf (tools/pamusb-conf), and pamusb-keyring-unlock-gnome (tools/pamusb-keyring-unlock-gnome). This vulnerability is fixed in 0.9.0.
Weakness: CWE-427
Which versions are affected by CVE-2026-47274?
How do I fix CVE-2026-47274?
No fix has been published for CVE-2026-47274 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-47274 being exploited?
There is no known exploitation of CVE-2026-47274 in the wild and no public exploit code.
Sources
Also known as GHSA-pp29-w28g-r9h9.