# CVE-2021-22600: linux: A double free bug in packet_set_ring() in net/packet/af_packet.c can be exploited by a local user through crafted sys...

CVE-2021-22600 is fixed in 12 products on 1 platform, first by DEBIAN-CVE-2021-22600, released January 26, 2022. It is being exploited: CISA added it to the Known Exploited Vulnerabilities catalog on April 11, 2022. Patch Radar priority: Patch now.

- Web page: https://patchblox.com/security/cve/CVE-2021-22600
- Priority: Patch now
- CVSS: 7.8 (high)
- EPSS: 0.0659
- CISA KEV: listed Apr 11, 2022, federal due date May 2, 2022
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jan 26, 2022

## Description

A double free bug in packet_set_ring() in net/packet/af_packet.c can be exploited by a local user through crafted syscalls to escalate privileges or deny service. We recommend upgrading kernel past the effected versions or rebuilding past ec6af094ea28f0f2dda1a6a33b14cd57e36a9755

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | kernel-uek ol 8 | 0:5.4.17-2136.306.1.3.el8uek | [ELSA-2022-9273](https://patchblox.com/security/data/fix/linux/elsa-2022-9273.md) | Apr 11, 2022 |
| Linux | kernel-uek-container ol 8 | 0:5.4.17-2136.306.1.3.el8 | [ELSA-2022-9274](https://patchblox.com/security/data/fix/linux/elsa-2022-9274.md) | Apr 11, 2022 |
| Linux | kernel-uek-container-debug ol 8 | 0:5.4.17-2136.306.1.3.el8 | [ELSA-2022-9274](https://patchblox.com/security/data/fix/linux/elsa-2022-9274.md) | Apr 11, 2022 |
| Linux | kernel-uek-debug ol 8 | 0:5.4.17-2136.306.1.3.el8uek | [ELSA-2022-9273](https://patchblox.com/security/data/fix/linux/elsa-2022-9273.md) | Apr 11, 2022 |
| Linux | kernel-uek-debug-devel ol 8 | 0:5.4.17-2136.306.1.3.el8uek | [ELSA-2022-9273](https://patchblox.com/security/data/fix/linux/elsa-2022-9273.md) | Apr 11, 2022 |
| Linux | kernel-uek-devel ol 8 | 0:5.4.17-2136.306.1.3.el8uek | [ELSA-2022-9273](https://patchblox.com/security/data/fix/linux/elsa-2022-9273.md) | Apr 11, 2022 |
| Linux | kernel-uek-doc ol 8 | 0:5.4.17-2136.306.1.3.el8uek | [ELSA-2022-9273](https://patchblox.com/security/data/fix/linux/elsa-2022-9273.md) | Apr 11, 2022 |
| Linux | kernel-uek-tools ol 8 | 0:5.4.17-2136.306.1.3.el7uek | [ELSA-2022-9273](https://patchblox.com/security/data/fix/linux/elsa-2022-9273.md) | Apr 11, 2022 |
| Linux | kernel-uek-tools-libs ol 8 | 0:5.4.17-2136.306.1.3.el7uek | [ELSA-2022-9273](https://patchblox.com/security/data/fix/linux/elsa-2022-9273.md) | Apr 11, 2022 |
| Linux | linux Debian 12.15 (bookworm) | 5.15.15-1 | [DEBIAN-CVE-2021-22600](https://patchblox.com/security/data/fix/linux/debian-cve-2021-22600.md) | Jan 26, 2022 |
| Linux | linux Debian 13.5 (trixie) | 5.15.15-1 | [DEBIAN-CVE-2021-22600](https://patchblox.com/security/data/fix/linux/debian-cve-2021-22600.md) | Jan 26, 2022 |
| Linux | linux Debian 14 | 5.15.15-1 | [DEBIAN-CVE-2021-22600](https://patchblox.com/security/data/fix/linux/debian-cve-2021-22600.md) | Jan 26, 2022 |
| Linux | perf ol 8 | 0:5.4.17-2136.306.1.3.el7uek | [ELSA-2022-9273](https://patchblox.com/security/data/fix/linux/elsa-2022-9273.md) | Apr 11, 2022 |
| Linux | python-perf ol 8 | 0:5.4.17-2136.306.1.3.el7uek | [ELSA-2022-9273](https://patchblox.com/security/data/fix/linux/elsa-2022-9273.md) | Apr 11, 2022 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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