CVE-2023-53276 ubifs: Free memory for tmpfile name
A memory leak in the Linux kernel UBIFS filesystem allows attackers to exhaust system memory by creating temporary files in encrypted directories.
- 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-2023-53276?
CVE-2023-53276 is a medium-severity memory corruption vulnerability in Linux kernel, published on 16 Sep 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:
ubifs: Free memory for tmpfile name
When opening a ubifs tmpfile on an encrypted directory, function fscrypt_setup_filename allocates memory for the name that is to be stored in the directory entry, but after the name has been copied to the directory entry inode, the memory is not freed.
When running kmemleak on it we see that it is registered as a leak. The report below is triggered by a simple program 'tmpfile' just opening a tmpfile:
unreferenced object 0xffff88810178f380 (size 32): comm "tmpfile", pid 509, jiffies 4294934744 (age 1524.742s) backtrace: __kmem_cache_alloc_node __kmalloc fscrypt_setup_filename ubifs_tmpfile vfs_tmpfile path_openat
Free this memory after it has been copied to the inode.
Weakness: CWE-401
Which versions are affected by CVE-2023-53276?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2023-53276?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2023-53276 being exploited?
There is no known exploitation of CVE-2023-53276 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2023-53276, DEBIAN-CVE-2023-53276, GHSA-jfrm-9rr7-r45w, UBUNTU-CVE-2023-53276.