CVE-2026-53227
MediumCVSS 5.5Exploitation Probability (EPSS)
Low risk3th percentile — higher than 3% of all known CVEs
Summary
In the Linux kernel, the Open vSwitch module has a vulnerability where kfree_skb can be called on an ERR_PTR pointer. This occurs when the reply buffer allocation happens after locking the mutex, and on failure the pointer is not cleared, leading to an attempt to free an invalid pointer.
Risk Assessment
This vulnerability can cause a kernel panic or unpredictable kernel behavior, posing a risk to the stability and availability of network services using Open vSwitch.
Recommendation
Apply the Linux kernel patch that sets the pointer to NULL after saving the error value. Update to a kernel version containing this fix as soon as possible.
Original NVD description (English source)
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.