# CVE-2021-4023: linux: A flaw was found in the io-workqueue implementation in the Linux kernel versions prior to 5.15-rc1

CVE-2021-4023 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-4023, released March 10, 2022. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-4023
- Priority: Routine
- CVSS: 5.5 (medium)
- EPSS: 0.0024
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Mar 10, 2022

## Description

A flaw was found in the io-workqueue implementation in the Linux kernel versions prior to 5.15-rc1. The kernel can panic when an improper cancellation operation triggers the submission of new io-uring operations during a shortage of free space. This flaw allows a local user with permissions to execute io-uring requests to possibly crash the system.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 5.15.3-1 | [DEBIAN-CVE-2021-4023](https://patchblox.com/security/data/fix/linux/debian-cve-2021-4023.md) | Mar 10, 2022 |
| Linux | linux Debian 13.5 (trixie) | 5.15.3-1 | [DEBIAN-CVE-2021-4023](https://patchblox.com/security/data/fix/linux/debian-cve-2021-4023.md) | Mar 10, 2022 |
| Linux | linux Debian 14 | 5.15.3-1 | [DEBIAN-CVE-2021-4023](https://patchblox.com/security/data/fix/linux/debian-cve-2021-4023.md) | Mar 10, 2022 |

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