Vulnerability in Linux

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]

EPSS: 0.002 (5.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Affected products

References

Frequently asked questions

What is CVE-2025-38686?
CVE-2025-38686 is a medium-severity vulnerability in Linux. CVSS score: 5.5/10. Published 2025-09-04.
How severe is CVE-2025-38686?
Medium severity. CVSS v3 base score is 5.5 out of 10.