PT-2025-35959 · Linux · Linux Kernel

Published 2025-09-04 · Updated 2025-09-04 · CVE-2025-38686

Positive Technologies · (AI Summary)

Name of the Vulnerable Software and Affected Versions:

Linux kernel (affected versions not specified)

Description:

A flaw exists in the Linux kernel related to userfaultfd. Specifically, a crash can occur in the `UFFDIO MOVE` operation when a Page Middle Directory (PMD) is a migration entry. The issue arises from attempting to obtain and access a folio even when the entry is a swap entry (`swp entry t`). The fix involves adding a check to handle migration entries correctly and removing an unnecessary folio check.

Recommendations:

At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Related Identifiers

CVE-2025-38686

Affected Products

Linux Kernel

References · 6

• https://nvd.nist.gov/vuln/detail/CVE-2025-38686 · Security Note
• https://twitter.com/CVEnew/status/1963644656123592965 · Twitter Post
• https://git.kernel.org/stable/c/aba6faec0103ed8f169be8dce2ead41fcb689446 · Note
• https://git.kernel.org/stable/c/bb81c18dbd42650c844e160cafa7cbb20243a96a · Note
• https://git.kernel.org/stable/c/1202abad7a7ccd28c426d2844771a387b07629a4 · Note
• https://git.kernel.org/stable/c/7f1101a0a181243ad587ececdffc4845f035549f · Note