CVE-2023-54050 ubifs: Fix memleak when insert_old_idx() failed
A memory leak in the Linux kernel UBIFS filesystem can lead to resource exhaustion and denial of service when index insertion fails.
- 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-2023-54050?
CVE-2023-54050 is a high-severity denial of service vulnerability in Linux, published on 24 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:
ubifs: Fix memleak when insert_old_idx() failed
Following process will cause a memleak for copied up znode:
dirty_cow_znode zn = copy_znode(c, znode); err = insert_old_idx(c, zbr->lnum, zbr->offs); if (unlikely(err)) return ERR_PTR(err); // No one refers to zn.
Fetch a reproducer in [Link].
Function copy_znode() is split into 2 parts: resource allocation and znode replacement, insert_old_idx() is split in similar way, so resource cleanup could be done in error handling path without corrupting metadata(mem & disk). It's okay that old index inserting is put behind of add_idx_dirt(), old index is used in layout_leb_in_gaps(), so the two processes do not depend on each other.
Which versions are affected by CVE-2023-54050?
How do I fix CVE-2023-54050?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2023-54050 being exploited?
There is no known exploitation of CVE-2023-54050 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-54050, DEBIAN-CVE-2023-54050, GHSA-4h8w-644c-qcrw, UBUNTU-CVE-2023-54050.