CVE-2026-22987 net/sched: act_api: avoid dereferencing ERR_PTR in tcf_idrinfo_destroy
A null pointer dereference in the Linux kernel's traffic control subsystem allows local attackers to cause a system crash during network namespace teardown.
- 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-2026-22987?
CVE-2026-22987 is a medium-severity vulnerability in Linux kernel, published on 23 Jan 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/sched: act_api: avoid dereferencing ERR_PTR in tcf_idrinfo_destroy
syzbot reported a crash in tc_act_in_hw() during netns teardown where tcf_idrinfo_destroy() passed an ERR_PTR(-EBUSY) value as a tc_action pointer, leading to an invalid dereference.
Guard against ERR_PTR entries when iterating the action IDR so teardown does not call tc_act_in_hw() on an error pointer.
Weakness: CWE-476
Which versions are affected by CVE-2026-22987?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-22987?
Apply the vendor's patch.
Is CVE-2026-22987 being exploited?
There is no known exploitation of CVE-2026-22987 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-22987, DEBIAN-CVE-2026-22987, GHSA-39xq-39v8-2g6g, UBUNTU-CVE-2026-22987.