CVE-2026-98062 bpf: Mark signal tracepoint siginfo arguments as scalar
A local attacker can trigger a kernel panic by dereferencing non-pointer signal tracepoint arguments in BPF programs.
- 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-2026-98062?
CVE-2026-98062 is a medium-severity vulnerability in Linux kernel, 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 signal tracepoint siginfo arguments as scalar
The signal_generate and signal_deliver tracepoints declare their info argument as a struct kernel_siginfo pointer. btf_ctx_access() therefore treats it as a trusted pointer for tp_btf programs.
Signal delivery also uses SEND_SIG_NOINFO and SEND_SIG_PRIV as special values for this argument. Those values are zero and one respectively, and are not pointers. A tp_btf program can currently dereference either value and fault the kernel. In particular, signal_generate can run from timer interrupt context, turning the fault into a kernel panic.
Record both tracepoints in raw_tp_null_args[] and mark argument one as a non-pointer. This preserves scalar access to the cookie while rejecting direct and helper-mediated pointer use. Merely marking it nullable would not suffice because SEND_SIG_PRIV is nonzero.
Weakness: CWE-476
Which versions are affected by CVE-2026-98062?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-98062?
Apply the vendor's patch.
Is CVE-2026-98062 being exploited?
There is no known exploitation of CVE-2026-98062 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-98062, DEBIAN-CVE-2026-98062, GHSA-x678-33cq-r6hr, UBUNTU-CVE-2026-98062.