CVE-2026-98046 bpf: Mark bpf_btf_find_by_name_kind() as sleepable
A local attacker can trigger a kernel crash by calling a BPF helper in a non-sleepable context, causing a denial of service.
- 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-2026-98046?
CVE-2026-98046 is a denial of service 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 bpf_btf_find_by_name_kind() as sleepable
When bpf_btf_find_by_name_kind() finds a type in module BTF, it returns a new BTF object fd through __btf_new_fd(). This reaches anon_inode_getfd(), which can sleep while allocating or expanding the current task fd table.
The helper prototype does not set might_sleep, so the verifier allows the helper in non-sleepable contexts such as BPF timer callbacks. The fd allocation can then sleep in softirq context and install the fd into the interrupted task.
Mark the helper as sleepable. This preserves calls from the main body of a sleepable syscall program while rejecting calls from its non-sleepable regions.
Which versions are affected by CVE-2026-98046?
How do I fix CVE-2026-98046?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-98046 being exploited?
There is no known exploitation of CVE-2026-98046 in the wild and no public exploit code.
Sources
Also known as AZL-104603, BELL-CVE-2026-98046, DEBIAN-CVE-2026-98046, GHSA-mcxj-647x-qcfv, UBUNTU-CVE-2026-98046.