CVE-2026-90358 bpf, x86: Fix trampoline stack size for 128-bit arguments
A stack buffer overflow in the Linux kernel BPF trampoline allows attackers to corrupt memory, potentially leading to code execution or privilege escalation.
- 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-2026-90358?
CVE-2026-90358 is a high-severity memory corruption 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:
bpf, x86: Fix trampoline stack size for 128-bit arguments
btf_distill_func_proto() accepts a function argument up to 16 bytes, so a 128-bit scalar such as __int128 reaches the x86 trampoline with arg_size == 16. But the current implementation assumes an __int128 argument only needs one register, so the register save area is under-allocated and save_args() overwrites adjacent stack slots.
Compute the register count from arg_size for all arguments to fix it.
Which versions are affected by CVE-2026-90358?
How do I fix CVE-2026-90358?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-90358 being exploited?
There is no known exploitation of CVE-2026-90358 in the wild and no public exploit code.
Sources
Also known as AZL-102515, BELL-CVE-2026-90358, DEBIAN-CVE-2026-90358, GHSA-4c82-vpvx-8vw4, UBUNTU-CVE-2026-90358.