CVE-2025-38686

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]

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/1202abad7a7ccd28c426d2844771a387b07629a4	Patch
https://git.kernel.org/stable/c/7f1101a0a181243ad587ececdffc4845f035549f	Patch
https://git.kernel.org/stable/c/aba6faec0103ed8f169be8dce2ead41fcb689446	Patch
https://git.kernel.org/stable/c/bb81c18dbd42650c844e160cafa7cbb20243a96a	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc1::::::

History

19 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta: userfaultfd: corregir un fallo en UFFDIO_MOVE cuando PMD es una entrada de migración Cuando UFFDIO_MOVE encuentra una entrada PMD de migración, procede a obtener un folio y acceder a él aunque la entrada es swp_entry_t. Añadir la comprobación faltante y dejar que split_huge_pmd() maneje las entradas de migración. Ya que estamos, también eliminar la comprobación de folio innecesaria. [surenb@google.com: eliminar comprobación de folio extra, según David]

Information

Published : 2025-09-04 16:15

Updated : 2026-10-19 21:10

NVD link : CVE-2025-38686

Mitre link : CVE-2025-38686

CVE.ORG link : CVE-2025-38686

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

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A\u00f1adir la comprobaci\u00f3n faltante y dejar que split_huge_pmd() maneje las entradas de migraci\u00f3n. Ya que estamos, tambi\u00e9n eliminar la comprobaci\u00f3n de folio innecesaria.\n\n[surenb@google.com: eliminar comprobaci\u00f3n de folio extra, seg\u00fan David]"}], "lastModified": "2026-10-19T21:10:00.160", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "169986BC-5A8A-4545-BC8B-EDA66328C234", "versionEndExcluding": "6.12.43", "versionStartIncluding": "6.8"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "BC242347-F722-43AE-B910-BE0B22386977", "versionEndExcluding": "6.15.11", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "BD7C087D-2415-4521-B624-30003352F899", "versionEndExcluding": "6.16.2", "versionStartIncluding": "6.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.17:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "327D22EF-390B-454C-BD31-2ED23C998A1C"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}