CVE-2025-38085

Published Jun 28, 2025

Last updated 3 months ago

CVSS medium 4.7

Overview

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.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel, debian_linux

Risk scores

CVSS 3.1

Type
Primary
Base score
4.7
Impact score
3.6
Exploitability score
1
Vector string
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
CWE-362

Social media

Hype score
Not currently trending

  1. (CVE-2025-38084, CVE-2025-38085)[mm/hugetlb]hugetlb page table sharing races with VMA splitting -> page table UAF https://t.co/YPwb3TZ3TX https://t.co/tZa2EyZUO7 https://t.co/blzX9U00JT Reported by Jann Horn(@tehjh )

    @xvonfers

    28 Jul 2025

    2696 Impressions

    8 Retweets

    42 Likes

    20 Bookmarks

    2 Replies

    0 Quotes

  2. CVE-2025-38085 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 pa… https://t.co/6kXky9Q39t

    @CVEnew

    28 Jun 2025

    532 Impressions

    0 Retweets

    0 Likes

    0 Bookmarks

    0 Replies

    0 Quotes

Configurations

Related CVEs

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References

Sources include official advisories and independent security research.