CVE-2026-46165 openvswitch: vport: fix self-deadlock on release of tunnel ports

What is CVE-2026-46165?

CVE-2026-46165 is a medium-severity vulnerability in Linux kernel, published on 28 May 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: vport: fix self-deadlock on release of tunnel ports

vports are used concurrently and protected by RCU, so netdev_put() must happen after the RCU grace period. So, either in an RCU call or after the synchronize_net(). The rtnl_delete_link() must happen under RTNL and so can't be executed in RCU context. Calling synchronize_net() while holding RTNL is not a good idea for performance and system stability under load in general, so calling netdev_put() in RCU call is the right solution here.

However, when the device is deleted, rtnl_unlock() will call netdev_run_todo() and block until all the references are gone. In the current code this means that we never reach the call_rcu() and the vport is never freed and the reference is never released, causing a self-deadlock on device removal.

Fix that by moving the rcu_call() before the rtnl_unlock(), so the scheduled RCU callback will be executed when synchronize_net() is called from the rtnl_unlock()->netdev_run_todo() while the RTNL itself is already released.

Weakness: CWE-667

Which versions are affected by CVE-2026-46165?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-46165?

Apply the vendor's patch.

Is CVE-2026-46165 being exploited?

There is no known exploitation of CVE-2026-46165 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-88821, BELL-CVE-2026-46165, DEBIAN-CVE-2026-46165, GHSA-gwmf-r7m2-pphm, ROOT-OS-DEBIAN-12-CVE-2026-46165, UBUNTU-CVE-2026-46165.