How severe is CVE-2026-43240?

CVE-2026-43240 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-43240 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-43240?

CVE-2026-43240 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-43240?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-43240 have an EU (EUVD) identifier?

Yes. CVE-2026-43240 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27799.

When was CVE-2026-43240 published?

CVE-2026-43240 was published on 2026-05-06 and last updated on 2026-06-19.

CVE-2026-43240

CVE-2026-43240 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (2nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-27799
Affected product: Linux Linux Kernel
Published: 2026-05-06
Last modified: 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.

Frequently asked questions

What is CVE-2026-43240?: 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.
How severe is CVE-2026-43240?: CVE-2026-43240 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-43240 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-43240?: CVE-2026-43240 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-43240?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-43240 have an EU (EUVD) identifier?: Yes. CVE-2026-43240 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27799.
When was CVE-2026-43240 published?: CVE-2026-43240 was published on 2026-05-06 and last updated on 2026-06-19.

References

Affected products (1)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

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