CVE-2026-72426 bpf: Preserve pointer spill metadata during half-slot cleanup
A flaw in the Linux kernel BPF verifier allows pointer spill metadata loss, potentially enabling memory corruption and privilege escalation.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-72426?
CVE-2026-72426 is a high-severity memory corruption vulnerability in Linux, published on 15 Aug 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: Preserve pointer spill metadata during half-slot cleanup
__clean_func_state() cleans dead stack slots in 4-byte halves. When the high half of a STACK_SPILL slot is dead and the low half remains live, cleanup converts the live low half to STACK_MISC or STACK_ZERO and clears the saved spilled_ptr metadata.
That conversion is safe only for scalar spills. For a pointer spill, this metadata clear lets a later 32-bit fill from the still-live half avoid the normal non-scalar register-fill check and be treated as an ordinary scalar stack read.
Leave non-scalar spill slots intact in this half-live shape. This is conservative for pruning and preserves the existing check_stack_read_fixed_off() rejection path for partial fills from pointer spills.
Which versions are affected by CVE-2026-72426?
How do I fix CVE-2026-72426?
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-2026-72426 being exploited?
There is no known exploitation of CVE-2026-72426 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-72426, GHSA-v693-v3px-mxpc, UBUNTU-CVE-2026-72426.