CVE-2026-72426: bpf: Preserve pointer spill metadata during half-slot cleanup
In the Linux kernel, the following vulnerability has been resolved:
bpf: Preserve pointer spill metadata during half-slot cleanup
cleanfuncstate() cleans dead stack slots in 4-byte halves. When the high half of a STACKSPILL slot is dead and the low half remains live, cleanup converts the live low half to STACKMISC or STACKZERO and clears the saved spilledptr 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 checkstackreadfixedoff() rejection path for partial fills from pointer spills.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-72426?
CVE-2026-72426 has a risk rating of 47.
How do I fix CVE-2026-72426?
To fix CVE-2026-72426, update the Linux kernel to the version that includes the patch for this vulnerability.
What systems are affected by CVE-2026-72426?
CVE-2026-72426 affects systems running vulnerable versions of the Linux kernel that utilize BPF (Berkeley Packet Filter).
What type of vulnerability is CVE-2026-72426?
CVE-2026-72426 is a vulnerability related to improper handling of pointer spill metadata during half-slot cleanup in the Linux kernel.
When was CVE-2026-72426 published?
CVE-2026-72426 was published on August 15, 2026.