CVE-2025-40291
High
io_uring: fix regbuf vector size truncation
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.
Exploit probability
0.1%
Published
December 8, 2025
Required by
Not available
Last source change
August 12, 2026
02 / AFFECTED SOFTWARE
Affected packages
04 / EVIDENCE
Source records
Open Source Vulnerabilities
CVE-2025-40291
View original source
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.
05 / REFERENCES
Further evidence
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/146eb58629f45f8297e83d69e64d4eea4b28d972
- https://git.kernel.org/stable/c/826ce37a842633efe1bb763e4b13045d74060d72
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/40xxx/CVE-2025-40291.json
- https://nvd.nist.gov/vuln/detail/CVE-2025-40291