CVE-2025-39727: linux kernel Buffer Overflow — Fix

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.

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CVSS v3.1 Score

7.8

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-120 CWE-120

Affected Products

Vendor	Product	Versions
linux	linux_kernel	6.12 — 6.12.42
linux	linux_kernel	6.13 — 6.15.10
linux	linux_kernel	6.16 — 6.16.1

References

Advisories & Patches

https://git.kernel.org/stable/c/152c1339dc13ad46f1b136e8693de15980750835 https://git.kernel.org/stable/c/815c528b13f2bb9b3130c13bedeabf2351a68129 https://git.kernel.org/stable/c/91b370800b3f2b3dda244c0ab06719c4971190a5 https://git.kernel.org/stable/c/9b01ada580ee84fb319e7ecb5fb5b1f54a9eb799

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. It has a CVSS v3.1 base score of 7.8 (HIGH).

How severe is CVE-2025-39727? +

CVE-2025-39727 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2025-39727? +

CVE-2025-39727 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-39727? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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