# CVE-2021-22600: Double Free in net/packet/af_packet.c leading to priviledge escalation

> CVE-2021-22600: Double Free in net/packet/af_packet.c leading to priviledge escalation. CVSS 6.6 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2021-22600
Last updated: 2025-10-21T23:15:48Z

- Published: 2022-01-26 00:00 UTC · Updated: 2025-10-21 23:15 UTC · Assigner: Google
- CVSS: 6.6 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:H
- EPSS: 6.6%, 94th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2022-04-11, federal due date 2022-05-02, ransomware use: Unknown
- CWE: CWE-415

## 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

## CISA required action

Apply updates per vendor instructions.

## Affected vendors and products

- Linux Kernel: Kernel

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2021-22600)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2021-22600)
- [https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=ec6af094ea28f0f2dda1a6a33b14cd57e36a9755](https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=ec6af094ea28f0f2dda1a6a33b14cd57e36a9755)
- [https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html](https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html)
- [https://security.netapp.com/advisory/ntap-20230110-0002/](https://security.netapp.com/advisory/ntap-20230110-0002/)
- [https://www.debian.org/security/2022/dsa-5096](https://www.debian.org/security/2022/dsa-5096)

---

_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


---
Canonical: https://rewindex.com/cve/CVE-2021-22600 · Markdown: https://rewindex.com/cve/CVE-2021-22600.md · JSON: https://rewindex.com/api/v1/cves/CVE-2021-22600 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T04:04:04.977Z