CVE-2026-43321 bpf: Properly mark live registers for indirect jumps
The Linux kernel BPF verifier incorrectly marked registers for indirect jumps, potentially leading to incorrect verification states or undefined behavior.
- 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-2026-43321?
CVE-2026-43321 is a high-severity vulnerability in Linux kernel, published on 8 May 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: Properly mark live registers for indirect jumps
For a `gotox rX` instruction the rX register should be marked as used in the compute_insn_live_regs() function. Fix this.
Weakness: CWE-682
Which versions are affected by CVE-2026-43321?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-43321?
Apply the vendor's patch.
Is CVE-2026-43321 being exploited?
There is no known exploitation of CVE-2026-43321 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-86166, GHSA-67fg-rv2j-g7r7, ROOT-OS-DEBIAN-11-CVE-2026-43321, ROOT-OS-DEBIAN-12-CVE-2026-43321, ROOT-OS-DEBIAN-13-CVE-2026-43321, ROOT-OS-UBUNTU-2204-CVE-2026-43321 and 2 more.