CVE-2025-38686
Full vulnerability record from the local CVENow database.
Description
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]
Severity
MEDIUM
CVSS score
5.5
(v3.1)
Vulnerability status
Analyzed
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2025-09-04 16:15:36.557000
Last modified
2026-10-19 21:10:00.160000
View original CVE JSON
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"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2025-09-04T16:15:36.557",
"lastModified": "2026-10-19T21:10:00.160",
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"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nuserfaultfd: fix a crash in UFFDIO_MOVE when PMD is a migration entry\n\nWhen UFFDIO_MOVE encounters a migration PMD entry, it proceeds with\nobtaining a folio and accessing it even though the entry is swp_entry_t. \nAdd the missing check and let split_huge_pmd() handle migration entries. \nWhile at it also remove unnecessary folio check.\n\n[[email protected]: remove extra folio check, per David]"
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"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nuserfaultfd: corregir un fallo en UFFDIO_MOVE cuando PMD es una entrada de migración\n\nCuando 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.\n\n[[email protected]: eliminar comprobación de folio extra, según David]"
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