CVE-2025-40364: Linux kernel · io_uring: fix io_req_prep_async with provided buffers
Source GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 13 Nov 2026, 19:20 UTC
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 18 Apr 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
A fix for this vulnerability has been implemented in the Linux kernel. Users and administrators should apply the official kernel updates that include this patch to remediate the issue. Since this is not a cloud service, manual patching is required. There are no known exploits in the wild at this time.
Description
A high-severity vulnerability in the Linux kernel's io_uring subsystem related to the io_req_prep_async function has been fixed. The flaw involved improper handling of provided buffers, where the function could commit the ring state prematurely and then reimport buffers later if needed. This could lead to serious impacts on confidentiality, integrity, and availability.
References
- nvd.nist.gov/vuln/detail/CVE-2025-40364 (opens in a new tab)
- git.kernel.org/stable/c/233b210a678bddf8b49b02a070074a52b87e6d43 (opens in a new tab)
- git.kernel.org/stable/c/35ae7910c349fb3c60439992e2e0e79061e95382 (opens in a new tab)
- git.kernel.org/stable/c/a1b17713b32c75a90132ea2f92b1257f3bbc20f3 (opens in a new tab)
- git.kernel.org/stable/c/a94592ec30ff67dc36c424327f1e0a9ceeeb9bd3 (opens in a new tab)
- git.kernel.org/stable/c/b86f1d51731e621e83305dc9564ae14c9ef752bf (opens in a new tab)
- git.kernel.org/stable/c/d63b0e8a628e62ca85a0f7915230186bb92f8bb4 (opens in a new tab)
- git.kernel.org/stable/c/f0ef94553868d07c1b14d7743a7e2553e5a831a3 (opens in a new tab)