CVE-2025-68185 nfs4_setup_readdir(): insufficient locking for ->d_parent->d_inode dereferencing
A race condition in the Linux kernel NFS client allows a local attacker to cause a system crash via insufficient locking during directory operations.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-68185?
CVE-2025-68185 is a vulnerability in Linux, published on 16 Dec 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
nfs4_setup_readdir(): insufficient locking for ->d_parent->d_inode dereferencing
Theoretically it's an oopsable race, but I don't believe one can manage to hit it on real hardware; might become doable on a KVM, but it still won't be easy to attack.
Anyway, it's easy to deal with - since xdr_encode_hyper() is just a call of put_unaligned_be64(), we can put that under ->d_lock and be done with that.
Which versions are affected by CVE-2025-68185?
How do I fix CVE-2025-68185?
Apply the vendor's patch.
Is CVE-2025-68185 being exploited?
There is no known exploitation of CVE-2025-68185 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2025-68185, DEBIAN-CVE-2025-68185, GHSA-6x57-w9x2-9hq7, ROOT-OS-DEBIAN-12-CVE-2025-68185, ROOT-OS-DEBIAN-13-CVE-2025-68185, ROOT-OS-UBUNTU-2204-CVE-2025-68185 and 2 more.