CVE-2023-53796 f2fs: fix information leak in f2fs_move_inline_dirents()
A local attacker can read uninitialized kernel memory from disk when converting inline directories in the f2fs filesystem.
- 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-2023-53796?
CVE-2023-53796 is a vulnerability in Linux, published on 9 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:
f2fs: fix information leak in f2fs_move_inline_dirents()
When converting an inline directory to a regular one, f2fs is leaking uninitialized memory to disk because it doesn't initialize the entire directory block. Fix this by zero-initializing the block.
This bug was introduced by commit 4ec17d688d74 ("f2fs: avoid unneeded initializing when converting inline dentry"), which didn't consider the security implications of leaking uninitialized memory to disk.
This was found by running xfstest generic/435 on a KMSAN-enabled kernel.
Which versions are affected by CVE-2023-53796?
How do I fix CVE-2023-53796?
Apply the vendor's patch.
Is CVE-2023-53796 being exploited?
There is no known exploitation of CVE-2023-53796 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-53796, DEBIAN-CVE-2023-53796, GHSA-g2pf-697j-2r49, UBUNTU-CVE-2023-53796.