CVE-2025-38686

CVE-2025-38686

Medium · published September 4, 2025

CVSS v3.1
5.5
EPSS
0%
Percentile
4.7
In the wild
Unconfirmed
What it is

In the Linux kernel, the following vulnerability has been resolved:

userfaultfd: fix a crash in UFFDIO_MOVE when PMD is a migration entry

When UFFDIO_MOVE encounters a migration PMD entry, it proceeds with

obtaining a folio and accessing it even though the entry is swp_entry_t.

Add the missing check and let split_huge_pmd() handle migration entries.

While at it also remove unnecessary folio check.

[[email protected]: remove extra folio check, per David]

The record
Technical detail
CVSS v3.1
5.5 · MEDIUM
Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00159 · 4.7th percentile
Published
2025-09-04T20:15Z
Affected products (4)
ProductVersionsFixed in
linux/linux_kernel≥ 6.8, < 6.12.436.12.43
linux/linux_kernel≥ 6.13, < 6.15.116.15.11
linux/linux_kernel≥ 6.16, < 6.16.26.16.2
linux/linux_kernelall versions—
References (4)
https://git.kernel.org/stable/c/1202abad7a7ccd28c426d2844771a387b07629a4 · 416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/7f1101a0a181243ad587ececdffc4845f035549f · 416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/aba6faec0103ed8f169be8dce2ead41fcb689446 · 416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/bb81c18dbd42650c844e160cafa7cbb20243a96a · 416baaa9-dc9f-4396-8d5f-8c081fb06d67
EPSS history
Timeline
  • 04 SEP 15:32Z
    userfaultfd: fix a crash in UFFDIO_MOVE when PMD is a migration entry
    cvelistv5