CVE-2025-40093 usb: gadget: f_ecm: Refactor bind path to use __free()
A NULL pointer dereference in the Linux kernel USB gadget driver can cause a system crash during specific bind/unbind cycles.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-40093?
CVE-2025-40093 is a high-severity vulnerability in Linux, published on 30 Oct 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_ecm: Refactor bind path to use __free()
After an bind/unbind cycle, the ecm->notify_req is left stale. If a subsequent bind fails, the unified error label attempts to free this stale request, leading to a NULL pointer dereference when accessing ep->ops->free_request.
Refactor the error handling in the bind path to use the __free() automatic cleanup mechanism.
Which versions are affected by CVE-2025-40093?
How do I fix CVE-2025-40093?
Apply the vendor's patch.
Is CVE-2025-40093 being exploited?
There is no known exploitation of CVE-2025-40093 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2025-40093, DEBIAN-CVE-2025-40093, GHSA-7jm9-29fh-9vrx, ROOT-OS-DEBIAN-11-CVE-2025-40093, ROOT-OS-DEBIAN-12-CVE-2025-40093, ROOT-OS-DEBIAN-13-CVE-2025-40093 and 3 more.