CVE-2025-68820 ext4: xattr: fix null pointer deref in ext4_raw_inode()
A null pointer dereference in the Linux kernel ext4 filesystem allows local attackers to cause a system crash via corrupted filesystem images.
- 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-2025-68820?
CVE-2025-68820 is a vulnerability in Linux, published on 13 Jan 2026. 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:
ext4: xattr: fix null pointer deref in ext4_raw_inode()
If ext4_get_inode_loc() fails (e.g. if it returns -EFSCORRUPTED), iloc.bh will remain set to NULL. Since ext4_xattr_inode_dec_ref_all() lacks error checking, this will lead to a null pointer dereference in ext4_raw_inode(), called right after ext4_get_inode_loc().
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Weakness: CWE-476
Which versions are affected by CVE-2025-68820?
How do I fix CVE-2025-68820?
Apply the vendor's patch.
Is CVE-2025-68820 being exploited?
There is no known exploitation of CVE-2025-68820 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2025-68820, DEBIAN-CVE-2025-68820, GHSA-mp4c-25vm-9w6p, ROOT-OS-UBUNTU-2204-CVE-2025-68820, ROOT-OS-UBUNTU-2404-CVE-2025-68820, UBUNTU-CVE-2025-68820.