CVE-2026-31678 openvswitch: defer tunnel netdev_put to RCU release
A race condition in the Linux kernel's Open vSwitch tunnel destruction can lead to a use-after-free, potentially causing a system crash.
- 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-2026-31678?
CVE-2026-31678 is a high-severity vulnerability in Linux kernel, published on 25 Apr 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:
openvswitch: defer tunnel netdev_put to RCU release
ovs_netdev_tunnel_destroy() may run after NETDEV_UNREGISTER already detached the device. Dropping the netdev reference in destroy can race with concurrent readers that still observe vport->dev.
Do not release vport->dev in ovs_netdev_tunnel_destroy(). Instead, let vport_netdev_free() drop the reference from the RCU callback, matching the non-tunnel destroy path and avoiding additional synchronization under RTNL.
Which versions are affected by CVE-2026-31678?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-31678?
Apply the vendor's patch.
Is CVE-2026-31678 being exploited?
There is no known exploitation of CVE-2026-31678 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-84216, BELL-CVE-2026-31678, DEBIAN-CVE-2026-31678, GHSA-x9m6-8j85-qvqg, ROOT-OS-DEBIAN-11-CVE-2026-31678, ROOT-OS-DEBIAN-12-CVE-2026-31678 and 3 more.