CVE-2026-43266
Description
In the Linux kernel, the following vulnerability has been resolved: EFI/CPER: don't go past the ARM processor CPER record buffer There's a logic inside GHES/CPER to detect if the section_length is too small, but it doesn't detect if it is too big. Currently, if the firmware receives an ARM processor CPER record stating that a section length is big, kernel will blindly trust section_length, producing a very long dump. For instance, a 67 bytes record with ERR_INFO_NUM set 46198 and section length set to 854918320 would dump a lot of data going a way past the firmware memory-mapped area. Fix it by adding a logic to prevent it to go past the buffer if ERR_INFO_NUM is too big, making it report instead: [Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 1 [Hardware Error]: event severity: recoverable [Hardware Error]: Error 0, type: recoverable [Hardware Error]: section_type: ARM processor error [Hardware Error]: MIDR: 0xff304b2f8476870a [Hardware Error]: section length: 854918320, CPER size: 67 [Hardware Error]: section length is too big [Hardware Error]: firmware-generated error record is incorrect [Hardware Error]: ERR_INFO_NUM is 46198 [ rjw: Subject and changelog tweaks ]
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.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| sles | affected | | |
| debian | bookworm | fixed | 6.1.170-1 |
| debian | forky | fixed | 6.19.6-1 |
| debian | sid | fixed | 6.19.6-1 |
| debian | trixie | fixed | 6.12.85-1 |
| linux-kernel | affected | 5.10.252 | |
| debian | bullseye | fixed | 5.10.257-1 |
References
- https://git.kernel.org/stable/c/25b290624b0e3d2f0f90238709ee0b6009b9fde8
- https://git.kernel.org/stable/c/45766863baf899059e75595dd3cb1116467f2095
- https://git.kernel.org/stable/c/64eb63f573f497553e1a0c388bbcdd639e0f0704
- https://git.kernel.org/stable/c/a68d22902a6916e10ee235fee609239004e129d0
- https://git.kernel.org/stable/c/be10c1bdf64a39832998f54900aa309b3917abcf
- https://git.kernel.org/stable/c/c80113dcfc807308f5ab33847fae77e07531aeb8
- https://git.kernel.org/stable/c/ca2aad8771aa9091bc9e42e7d546bd40b72ddcd4
- https://git.kernel.org/stable/c/eae21beecb95a3b69ee5c38a659f774e171d730e
- https://www.suse.com/security/cve/CVE-2026-43266.html
- https://security-tracker.debian.org/tracker/CVE-2026-43266
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.