How severe is CVE-2025-39727?

CVE-2025-39727 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-39727 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-39727?

CVE-2025-39727 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-39727?

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-2025-39727 have an EU (EUVD) identifier?

Yes. CVE-2025-39727 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-31502.

When was CVE-2025-39727 published?

CVE-2025-39727 was published on 2025-09-07 and last updated on 2026-06-17.

CVE-2025-39727

CVE-2025-39727 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-120.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 0% (6th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-31502
Weakness: CWE-120
Affected product: Linux Linux Kernel
Published: 2025-09-07
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: mm: swap: fix potential buffer overflow in setup_clusters() In setup_swap_map(), we only ensure badpages are in range (0, last_page]. As maxpages might be < last_page, setup_clusters() will encounter a buffer overflow when a badpage is >= maxpages. Only call inc_cluster_info_page() for badpage which is < maxpages to fix the issue.

Frequently asked questions

What is CVE-2025-39727?: In the Linux kernel, the following vulnerability has been resolved: mm: swap: fix potential buffer overflow in setup_clusters() In setup_swap_map(), we only ensure badpages are in range (0, last_page]. As maxpages might be < last_page, setup_clusters() will encounter a buffer overflow when a badpage is >= maxpages. Only call inc_cluster_info_page() for badpage which is < maxpages to fix the issue.
How severe is CVE-2025-39727?: CVE-2025-39727 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-39727 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-39727?: CVE-2025-39727 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-39727?: 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-2025-39727 have an EU (EUVD) identifier?: Yes. CVE-2025-39727 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-31502.
When was CVE-2025-39727 published?: CVE-2025-39727 was published on 2025-09-07 and last updated on 2026-06-17.

References

Affected products (1)

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

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