CVE-2026-72428
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix stack slot index in nospec checks check_stack_write_fixed_off() computes the byte slot for a fixed-offset stack write as -off - 1, and records each written byte in slot_type[] with (slot - i) % BPF_REG_SIZE. The Spectre v4 sanitization pre-check uses slot_type[i] instead. For a 4-byte write at fp-8 after the lower half of fp-8 has been zeroed, the pre-check scans bytes 0..3 and sees STACK_ZERO while the actual write updates bytes 7..4. That can leave the second half-slot write without nospec_result even though the bytes being overwritten still require sanitization. Use the same slot index in the sanitization pre-check that the write path uses when updating slot_type[].
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
References
- https://git.kernel.org/stable/c/475405593de2b796224c6297aece44f321195919
- https://git.kernel.org/stable/c/68b41e68a62299f26cb16af422b5c7d1c69dafd9
- https://git.kernel.org/stable/c/a71eb8f730a91271cf47ce291e785b6b7e54622f
- https://git.kernel.org/stable/c/ca119656baa8f48a56e0c2f3ab63fdd33ca9e307
- https://git.kernel.org/stable/c/d1d53aa30ab3b5ae89161c9cc840b3f7489ad386
- https://git.kernel.org/stable/c/db8f1dcf5950b91886b9df4270bc816370d292c1
- https://git.kernel.org/stable/c/e62268e695075a481a6c4feeb022c19cf57422a6
- https://git.kernel.org/stable/c/f1471aa76d74e0df3b2a90731ca0208f498c670b
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.