CVE-2025-68212 fs: Fix uninitialized 'offp' in statmount_string()
A local attacker can cause a kernel crash by triggering an uninitialized pointer dereference in the statmount_string function.
- 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-2025-68212?
CVE-2025-68212 is a high-severity vulnerability in Linux, published on 16 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:
fs: Fix uninitialized 'offp' in statmount_string()
In statmount_string(), most flags assign an output offset pointer (offp) which is later updated with the string offset. However, the STATMOUNT_MNT_UIDMAP and STATMOUNT_MNT_GIDMAP cases directly set the struct fields instead of using offp. This leaves offp uninitialized, leading to a possible uninitialized dereference when *offp is updated.
Fix it by assigning offp for UIDMAP and GIDMAP as well, keeping the code path consistent.
Which versions are affected by CVE-2025-68212?
How do I fix CVE-2025-68212?
Apply the vendor's patch.
Is CVE-2025-68212 being exploited?
There is no known exploitation of CVE-2025-68212 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2025-68212, DEBIAN-CVE-2025-68212, GHSA-qh7q-6f85-cjv9, ROOT-OS-UBUNTU-2404-CVE-2025-68212, UBUNTU-CVE-2025-68212.