CVE-2026-43240: x86/kexec: add a sanity check on previous kernel's ima kexec buffer

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 2026-06-19

Description

In the Linux kernel, the following vulnerability has been resolved: x86/kexec: add a sanity check on previous kernel's ima kexec buffer When the second-stage kernel is booted via kexec with a limiting command line such as "mem=<size>", the physical range that contains the carried over IMA measurement list may fall outside the truncated RAM leading to a kernel panic. BUG: unable to handle page fault for address: ffff97793ff47000 RIP: ima_restore_measurement_list+0xdc/0x45a #PF: error_code(0x0000) – not-present page Other architectures already validate the range with page_is_ram(), as done in commit cbf9c4b9617b ("of: check previous kernel's ima-kexec-buffer against memory bounds") do a similar check on x86. Without carrying the measurement list across kexec, the attestation would fail.

Affected products

Linux kernel: from 6.0 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; from 6.19 before 6.19.6 — fixed in 6.1.165, 6.12.75, 6.18.16, 6.19.6, 6.6.128

How to fix

Upgrade to a fixed version: Linux kernel 6.1.165, 6.12.75, 6.18.16, 6.19.6. Check the vendor advisory for mitigations.

References

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