CVE-2025-38242: Linux kernel · Race Condition
Source GCVE Database
Not known to be exploited · CVSS 4.7 Medium.
Data as of 13 Nov 2026, 20:33 UTC
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 9 Jul 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
AI-suggested
Until a fix is applied, users should be aware of the potential for kernel instability when using userfaultfd with swap cache operations. Monitor vendor communications for updates and apply kernel updates once available.
Description
CVE-2025-38242 is a race condition vulnerability in the Linux kernel's userfaultfd subsystem related to the move of swap cache entries. It involves a race between userfaultfd_move and swap cache operations that can cause kernel BUGs and corrupted RSS counters. The flaw arises from unreliable checks when moving folios in the swap cache, potentially leading to accounting errors. While data corruption is not confirmed, the issue can cause kernel instability and crashes.
References
- nvd.nist.gov/vuln/detail/CVE-2025-38242 (opens in a new tab)
- git.kernel.org/stable/c/0ea148a799198518d8ebab63ddd0bb6114a103bc (opens in a new tab)
- git.kernel.org/stable/c/4c443046d8c9ed8724a4f4c3c2457d3ac8814b2f (opens in a new tab)
- git.kernel.org/stable/c/db2ca8074955ca64187a4fb596dd290b9c446cd3 (opens in a new tab)