CVE-2026-53227 net: openvswitch: fix possible kfree_skb of ERR_PTR
A flaw in the Linux kernel's Open vSwitch module allows a local attacker to cause a denial of service by triggering an invalid memory free operation.
- 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-2026-53227?
CVE-2026-53227 is a medium-severity vulnerability in Linux kernel, published on 25 Jun 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:
net: openvswitch: fix possible kfree_skb of ERR_PTR
After the patch in the "Fixes" tag, the allocation of the "reply" skb can happen either before or after locking the ovs_mutex.
However, error cleanups still follow the classical reversed order, assuming "reply" is allocated before locking: it is freed after unlocking.
If "reply" allocation happens after locking the mutex and it fails, "reply" is left with an ERR_PTR, and execution jumps to the correspondent cleanup stage which will try to free an invalid pointer.
Fix this by setting the pointer to NULL after having saved its error value.
Weakness: CWE-401
Which versions are affected by CVE-2026-53227?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-53227?
Apply the vendor's patch.
Is CVE-2026-53227 being exploited?
There is no known exploitation of CVE-2026-53227 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-90860, BELL-CVE-2026-53227, DEBIAN-CVE-2026-53227, GHSA-mp79-8qq6-qp9g, ROOT-OS-DEBIAN-11-CVE-2026-53227, ROOT-OS-DEBIAN-12-CVE-2026-53227 and 3 more.