CVE-2021-47040
Medium
Elevated severity or exploit probability.
CVSS base
7.8
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS — probability of exploitation (30 days)
0.3%
18.0th percentile
CISA KEV
Not listed
Weakness / dates
CWE-120
Published 2024-02-28 · modified 2026-08-04
CVSS breakdown
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
| Attack Vector | L | Local |
| Attack Complexity | L | Low |
| Privileges Required | L | Low |
| User Interaction | N | None |
| Scope | U | Unchanged |
| Confidentiality | H | High |
| Integrity | H | High |
| Availability | H | High |
Timeline
- 2024-02-28 — Published (NVD)
- 2026-08-04 — Last modified (NVD)
Description
In the Linux kernel, the following vulnerability has been resolved: io_uring: fix overflows checks in provide buffers Colin reported before possible overflow and sign extension problems in io_provide_buffers_prep(). As Linus pointed out previous attempt did nothing useful, see d81269fecb8ce ("io_uring: fix provide_buffers sign extension"). Do that with help of check_<op>_overflow helpers. And fix struct io_provide_buf::len type, as it doesn't make much sense to keep it signed.
Affected
References
- https://git.kernel.org/stable/c/38134ada0ceea3e848fe993263c0ff6207fd46e7
- https://git.kernel.org/stable/c/51bf90901952aaac564bbdb36b2b503050c53dd9
- https://git.kernel.org/stable/c/84b8c266c4bfe9ed5128e13253c388deb74b1b03
- https://git.kernel.org/stable/c/cbbc13b115b8f18e0a714d89f87fbdc499acfe2d
- https://git.kernel.org/stable/c/38134ada0ceea3e848fe993263c0ff6207fd46e7
- https://git.kernel.org/stable/c/51bf90901952aaac564bbdb36b2b503050c53dd9
- https://git.kernel.org/stable/c/84b8c266c4bfe9ed5128e13253c388deb74b1b03
- https://git.kernel.org/stable/c/cbbc13b115b8f18e0a714d89f87fbdc499acfe2d