CVE-2021-22600

MEDIUM KEV

Linux Kernel - Privilege Escalation

Title source: llm
STIX 2.1

Exploitation Summary

CVE-2021-22600 is actively exploited and listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added April 11, 2022. EIP tracks 2 public exploits from researchers including Chinmay1743, sendINUX.

AI-analyzed exploit summary This repository provides a technical analysis and privilege probe for CVE-2021-22600, demonstrating how AF_PACKET socket creation and PACKET_RX_RING configuration behave under different privilege levels (user vs. root). It includes a detailed explanation of kernel checks for CAP_NET_RAW and the implications of exploitation.

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

Exploits (2)

nomisec WRITEUP
by Chinmay1743 · local
https://github.com/Chinmay1743/af_packet.c

This repository provides a technical analysis and privilege probe for CVE-2021-22600, demonstrating how AF_PACKET socket creation and PACKET_RX_RING configuration behave under different privilege levels (user vs. root). It includes a detailed explanation of kernel checks for CAP_NET_RAW and the implications of exploitation.

Classification
Writeup 90%
Attack Type
Other
Complexity
Moderate
Reliability
Reliable
Target: Linux kernel (af_packet.c)
No auth needed
Prerequisites: Access to a Linux system with AF_PACKET sockets · Basic understanding of Linux capabilities
devstral-2 · analyzed Feb 18, 2026 Full analysis →
nomisec WORKING POC
by sendINUX · local
https://github.com/sendINUX/CVE-2021-22600__DirtyPagetable

This repository contains functional exploit code for CVE-2021-22600, leveraging the DirtyPagetable technique to achieve local privilege escalation (LPE) in the Linux kernel. The exploit involves manipulating kernel memory structures through socket operations and signalfd spraying.

Classification
Working Poc 95%
Attack Type
Lpe
Complexity
Complex
Reliability
Racy
Target: Linux kernel (specific versions affected by CVE-2021-22600)
No auth needed
Prerequisites: Local access to the vulnerable system · Kernel version vulnerable to CVE-2021-22600
devstral-2 · analyzed Feb 18, 2026 Full analysis →

Scores

CVSS v3 6.6
EPSS 0.0592
EPSS Percentile 92.3%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:H

CISA SSVC

Vulnrichment
Exploitation active
Automatable no
Technical Impact partial

Details

CISA KEV 2022-04-11
VulnCheck KEV 2022-03-07
InTheWild.io 2022-03-07
ENISA EUVD EUVD-2021-9736
CWE
CWE-415
Status published
Products (12)
debian/debian_linux 9.0
debian/debian_linux 10.0
linux/linux_kernel 4.14.175 - 4.14.259
netapp/8300_firmware
netapp/8700_firmware
netapp/a400_firmware
netapp/c400_firmware
netapp/h300s_firmware
netapp/h410c_firmware
netapp/h410s_firmware
... and 2 more
Published Jan 26, 2022
KEV Added Apr 11, 2022
Tracked Since Feb 18, 2026