CVE-2026-98019 bpf: mark a NULL call argument precise
A flaw in the Linux kernel BPF verifier allows bypassing precision checks, potentially leading to privilege escalation for local attackers.
- 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-2026-98019?
CVE-2026-98019 is a vulnerability in Linux, published on 25 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:
bpf: mark a NULL call argument precise
check_func_arg() allows bpf_register_is_null() for nullable arguments w/o marking the underlying scalar register precise. Hence a checkpoint created on such a path would prune against arbitrary scalar value.
check_helper_call() enforces second parameter of the bpf_get_local_storage() to be zero, w/o marking the underlying scalar register precise. Hence a checkpoint created on such a path would prune against arbitrary scalar value.
Grouping these two into one patch, as they share the same fixes tag.
Which versions are affected by CVE-2026-98019?
How do I fix CVE-2026-98019?
Apply the vendor's patch.
Is CVE-2026-98019 being exploited?
There is no known exploitation of CVE-2026-98019 in the wild and no public exploit code.
Sources
Also known as AZL-104519, BELL-CVE-2026-98019, DEBIAN-CVE-2026-98019, GHSA-cgv7-rwvp-jx5m, UBUNTU-CVE-2026-98019.