CVE-2026-89588: ACPI: APEI: GHES: fix ARM section length accounting after header

Severity: high (CVSS 8.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-11 · updated 2026-10-19

Description

In the Linux kernel, the following vulnerability has been resolved: ACPI: APEI: GHES: fix ARM section length accounting after header In ghes_handle_arm_hw_error(), after skipping the cper_sec_proc_arm header with (err + 1), the remaining length was reduced by sizeof(err) (pointer size) instead of sizeof(*err) (structure size). That overestimates the bytes left for cper_arm_err_info records and can let the parser read past the CPER section when err_info_num is large enough relative to error_data_length. Use sizeof(*err) so the length accounting matches the pointer advance and the earlier sizeof(*err) size check.

Affected products

Linux kernel: from 6.12.75 before 6.12.109; from 6.18.16 before 6.18.50; from 6.19.6 before 6.20; 7.0 — fixed in 6.12.109, 6.18.50, 6.20, 7.3

How to fix

Upgrade to a fixed version: Linux kernel 6.12.109, 6.18.50, 6.20, 7.3. Check the vendor advisory for mitigations.

References

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