How severe is CVE-2026-45955?

CVE-2026-45955 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.

Is CVE-2026-45955 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-45955?

CVE-2026-45955 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-45955?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-45955 have an EU (EUVD) identifier?

Yes. CVE-2026-45955 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-32239.

When was CVE-2026-45955 published?

CVE-2026-45955 was published on 2026-05-27 and last updated on 2026-06-17.

CVE-2026-45955

CVE-2026-45955 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 7.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 3.x base score 7.1)
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-32239
Affected product: Linux Linux Kernel
Published: 2026-05-27
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: md/md-llbitmap: fix percpu_ref not resurrected on suspend timeout When llbitmap_suspend_timeout() times out waiting for percpu_ref to become zero, it returns -ETIMEDOUT without resurrecting the percpu_ref. The caller (md_llbitmap_daemon_fn) then continues to the next page without calling llbitmap_resume(), leaving the percpu_ref in a killed state permanently. Fix this by resurrecting the percpu_ref before returning the error, ensuring the page control structure remains usable for subsequent operations.

Frequently asked questions

What is CVE-2026-45955?: In the Linux kernel, the following vulnerability has been resolved: md/md-llbitmap: fix percpu_ref not resurrected on suspend timeout When llbitmap_suspend_timeout() times out waiting for percpu_ref to become zero, it returns -ETIMEDOUT without resurrecting the percpu_ref. The caller (md_llbitmap_daemon_fn) then continues to the next page without calling llbitmap_resume(), leaving the percpu_ref in a killed state permanently. Fix this by resurrecting the percpu_ref before returning the error, ensuring the page control structure remains usable for subsequent operations.
How severe is CVE-2026-45955?: CVE-2026-45955 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.
Is CVE-2026-45955 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-45955?: CVE-2026-45955 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-45955?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-45955 have an EU (EUVD) identifier?: Yes. CVE-2026-45955 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-32239.
When was CVE-2026-45955 published?: CVE-2026-45955 was published on 2026-05-27 and last updated on 2026-06-17.

References

Affected products (1)

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

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