CVE-2026-90143 net: kcm: Hold RCU read lock while running BPF parser
Missing RCU lock in Linux kernel KCM BPF parser can trigger warnings and potential instability, requiring a kernel patch.
- 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-2026-90143?
CVE-2026-90143 is a high-severity vulnerability in Linux, published on 17 Sep 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: kcm: Hold RCU read lock while running BPF parser
kcm_parse_func_strparser() calls bpf_prog_run_pin_on_cpu() which prevents CPU migration, but does not establish an RCU read-side critical section. Consequently, BPF map operations can trigger WARN_ON_ONCE(!bpf_rcu_lock_held()) when called from the KCM strparser program.
Hold the RCU read lock while running the program.
Which versions are affected by CVE-2026-90143?
How do I fix CVE-2026-90143?
Apply the vendor's patch.
Is CVE-2026-90143 being exploited?
There is no known exploitation of CVE-2026-90143 in the wild and no public exploit code.
Sources
Also known as AZL-102017, BELL-CVE-2026-90143, DEBIAN-CVE-2026-90143, GHSA-f8r4-w3wx-2xx3, UBUNTU-CVE-2026-90143.