# CVE-2023-21400: linux: In multiple functions  of io_uring.c, there is a possible kernel memory corruption due to improper locking

CVE-2023-21400 is fixed in linux on 1 platform, first by DEBIAN-CVE-2023-21400, released July 13, 2023. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2023-21400
- Priority: Routine
- CVSS: 6.7 (medium)
- EPSS: 0.0026
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jul 13, 2023

## Description

In multiple functions  of io_uring.c, there is a possible kernel memory corruption due to improper locking. This could lead to local escalation of privilege in the kernel with System execution privileges needed. User interaction is not needed for exploitation.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 5.18.2-1 | [DEBIAN-CVE-2023-21400](https://patchblox.com/security/data/fix/linux/debian-cve-2023-21400.md) | Jul 13, 2023 |
| Linux | linux Debian 13.5 (trixie) | 5.18.2-1 | [DEBIAN-CVE-2023-21400](https://patchblox.com/security/data/fix/linux/debian-cve-2023-21400.md) | Jul 13, 2023 |
| Linux | linux Debian 14 | 5.18.2-1 | [DEBIAN-CVE-2023-21400](https://patchblox.com/security/data/fix/linux/debian-cve-2023-21400.md) | Jul 13, 2023 |

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