High 7.8Published Dec 7, 2025

CVE-2025-40291io_uring: fix regbuf vector size truncation

Updated under an hour ago (Oct 27, 2026, 2:50 AM ET)

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No exploitation reported and no EPSS estimate yet.

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Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: io_uring: fix regbuf vector size truncation There is a report of io_estimate_bvec_size() truncating the calculated number of segments that leads to corruption issues. Check it doesn't overflow "int"s used later. Rough but simple, can be improved on top.

CVSS: 7.8 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): Not given
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Deferred
Record last updated: Aug 5, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from 9ef4cbbcb4ac3786a1a4164507511b76b2a572c5 before 826ce37a842633efe1bb763e4b13045d74060d72; from 9ef4cbbcb4ac3786a1a4164507511b76b2a572c5 before 146eb58629f45f8297e83d69e64d4eea4b28d972	CNA record

References

References

https://git.kernel.org/stable/c/826ce37a842633efe1bb763e4b13045d74060d72
https://git.kernel.org/stable/c/146eb58629f45f8297e83d69e64d4eea4b28d972

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.