CVE-2026-53334 mm/damon/reclaim: handle ctx allocation failure
A null pointer dereference in the Linux kernel DAMON reclaim module can cause a system crash if memory allocation 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-2026-53334?
CVE-2026-53334 is a medium-severity vulnerability in Linux kernel, published on 1 Jul 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:
mm/damon/reclaim: handle ctx allocation failure
Patch series "mm/damon/{reclaim,lru_sort}: handle ctx allocation failures".
DAMON_RECLAIM and DAMON_LRU_SORT could dereference NULL pointers if their damon_ctx object allocations fail. The bugs are expected to happen infrequently because the allocations are arguably too small to fail on common setups. But theoretically they are possible and the consequences are bad. Fix those.
The issues were discovered [1] by Sashiko.
This patch (of 2):
DAMON_RECLAIM allocates the damon_ctx object for its kdamond in its init function. damon_reclaim_enabled_store() wrongly assumes the allocation will always succeed once tried. If the damon_ctx allocation was failed, therefore, code execution reaches to damon_commit_ctx() while 'ctx' is NULL. As a result, it dereferences the NULL 'ctx' pointer. Avoid the NULL dereference by returning -ENOMEM if 'ctx' is NULL.
Weakness: CWE-476
Which versions are affected by CVE-2026-53334?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-53334?
Apply the vendor's patch.
Is CVE-2026-53334 being exploited?
There is no known exploitation of CVE-2026-53334 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-53334, DEBIAN-CVE-2026-53334, GHSA-q79f-r3xp-pp5m, UBUNTU-CVE-2026-53334.