CVE-2025-38686

CVE-2025-38686 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

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]

Frequently asked questions

What is 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. [[email protected]: remove extra folio check, per David]
How severe is CVE-2025-38686?
CVE-2025-38686 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-38686 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-38686?
CVE-2025-38686 primarily affects Linux Linux Kernel. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-38686?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-38686 have an EU (EUVD) identifier?
Yes. CVE-2025-38686 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-26783.
When was CVE-2025-38686 published?
CVE-2025-38686 was published on 2025-09-04 and last updated on 2026-06-17.

References

Affected products (2)

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