CVE-2025-38085

4.7 MEDIUM
Published: June 28, 2025 Modified: December 18, 2025

Description

In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: fix huge_pmd_unshare() vs GUP-fast race huge_pmd_unshare() drops a reference on a page table that may have previously been shared across processes, potentially turning it into a normal page table used in another process in which unrelated VMAs can afterwards be installed. If this happens in the middle of a concurrent gup_fast(), gup_fast() could end up walking the page tables of another process. While I don't see any way in which that immediately leads to kernel memory corruption, it is really weird and unexpected. Fix it with an explicit broadcast IPI through tlb_remove_table_sync_one(), just like we do in khugepaged when removing page tables for a THP collapse.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://git.kernel.org/stable/c/034a52b5ef57c9c8225d94e9067f3390bb33922f
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/1013af4f585fccc4d3e5c5824d174de2257f7d6d
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/952596b08c74e8fe9e2883d1dc8a8f54a37384ec
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/a3d864c901a300c295692d129159fc3001a56185
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/a6bfeb97941a9187833b526bc6cc4ff5706d0ce9
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/b7754d3aa7bf9f62218d096c0c8f6c13698fac8b
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/fe684290418ef9ef76630072086ee530b92f02b8
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://project-zero.issues.chromium.org/issues/420715744
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Third Party Advisory
https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory

10 reference(s) from NVD

Quick Stats

CVSS v3 Score
4.7 / 10.0
EPSS (Exploit Probability)
0.0%
5th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

debian linux