CVE-2026-43171: EFI/CPER: don't dump the entire memory region

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-06 · updated 2026-06-17
Weakness: CWE-191

Description

In the Linux kernel, the following vulnerability has been resolved: EFI/CPER: don't dump the entire memory region The current logic at cper_print_fw_err() doesn't check if the error record length is big enough to handle offset. On a bad firmware, if the ofset is above the actual record, length -= offset will underflow, making it dump the entire memory. The end result can be: - the logic taking a lot of time dumping large regions of memory; - data disclosure due to the memory dumps; - an OOPS, if it tries to dump an unmapped memory region. Fix it by checking if the section length is too small before doing a hex dump. [ rjw: Subject tweaks ]

Affected products

Linux kernel: from 5.7 (excl.) before 5.10.252; from 5.11 before 5.15.202; from 5.16 before 6.1.165; from 6.2 before 6.6.128; from 6.7 before 6.12.75; from 6.13 before 6.18.16 — fixed in 5.10.252, 5.15.202, 6.1.165, 6.12.75, 6.18.16, 6.19.6

How to fix

Upgrade to a fixed version: Linux kernel 5.10.252, 5.15.202, 6.1.165, 6.12.75. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2026-43171 or the next vulnerability affects your stack