CVE-2025-38686 (GCVE-0-2025-38686)

Vulnerability from cvelistv5 – Published: 2025-09-04 15:32 – Updated: 2026-05-11 21:33
VLAI
Title
userfaultfd: fix a crash in UFFDIO_MOVE when PMD is a migration entry
Summary
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. [surenb@google.com: remove extra folio check, per David]
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6971 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: adef440691bab824e39c1b17382322d195e1fab0 , < bb81c18dbd42650c844e160cafa7cbb20243a96a (git)
Affected: adef440691bab824e39c1b17382322d195e1fab0 , < 1202abad7a7ccd28c426d2844771a387b07629a4 (git)
Affected: adef440691bab824e39c1b17382322d195e1fab0 , < 7f1101a0a181243ad587ececdffc4845f035549f (git)
Affected: adef440691bab824e39c1b17382322d195e1fab0 , < aba6faec0103ed8f169be8dce2ead41fcb689446 (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.8
Unaffected: 0 , < 6.8 (semver)
Unaffected: 6.12.43 , ≤ 6.12.* (semver)
Unaffected: 6.15.11 , ≤ 6.15.* (semver)
Unaffected: 6.16.2 , ≤ 6.16.* (semver)
Unaffected: 6.17 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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}



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