CVE-2026-48792 Security feature bypass in pam usb
Attackers can bypass USB-based hardware authentication on Linux systems by exploiting a flaw where permission errors are ignored during device scanning.
- 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-2026-48792?
CVE-2026-48792 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 0.9.1, src/evdev.c silently ignores EACCES errors when opening /dev/input/event* nodes, causing pusb_has_virtual_input_device() to return 0 (no virtual devices found) even when every open() call failed due to insufficient permissions. The caller in src/local.c cannot distinguish a clean absence of virtual devices from a permission-denied scan, and acts on the false negative by continuing authentication without denying. This vulnerability is fixed in 0.9.1.
Which versions are affected by CVE-2026-48792?
How do I fix CVE-2026-48792?
No fix has been published for CVE-2026-48792 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-48792 being exploited?
There is no known exploitation of CVE-2026-48792 in the wild and no public exploit code.
Sources
Also known as GHSA-pvrg-chgw-x42c.