CVE-2025-40291: Linux

High severity, CVSS 7.8. EPSS: 0.1% chance of exploitation in the next 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.

Affected products

• Linux Linux: from 6.15, before 6.17.8 (fixed in 6.17.8)

Published 2025-12-08. Last modified 2026-07-30.