CVE-2025-40299 gve: Implement gettimex64 with -EOPNOTSUPP
A missing function implementation in the gve network driver causes a null pointer dereference, leading to a kernel crash and denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-40299?
CVE-2025-40299 is a vulnerability in Linux, published on 8 Dec 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:
gve: Implement gettimex64 with -EOPNOTSUPP
gve implemented a ptp_clock for sole use of do_aux_work at this time. ptp_clock_gettime() and ptp_sys_offset() assume every ptp_clock has implemented either gettimex64 or gettime64. Stub gettimex64 and return -EOPNOTSUPP to prevent NULL dereferencing.
Which versions are affected by CVE-2025-40299?
How do I fix CVE-2025-40299?
Apply the vendor's patch.
Is CVE-2025-40299 being exploited?
There is no known exploitation of CVE-2025-40299 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2025-40299, DEBIAN-CVE-2025-40299, GHSA-3x8g-vpq9-jv7h, UBUNTU-CVE-2025-40299.