CVE-2021-22600
Published: April 11, 2022
Official Description
Linux Kernel contains a flaw in the packet socket (AF_PACKET) implementation which could lead to incorrectly freeing memory. A local user could exploit this for denial-of-service (DoS) or possibly for privilege escalation.
CISA KEV Advisory
Linux Kernel Privilege Escalation Vulnerability
Linux Kernel contains a flaw in the packet socket (AF_PACKET) implementation which could lead to incorrectly freeing memory. A local user could exploit this for denial-of-service (DoS) or possibly for privilege escalation.
Apply updates per vendor instructions.
Risk Analysis
A flaw in the Linux Kernel's packet socket implementation can lead to memory being freed incorrectly. This could result in a denial-of-service or potentially privilege escalation for a local user. Despite a low EPSS score, its presence in CISA's KEV catalog and active exploitation make it a critical concern.
This vulnerability is actively exploited in the wild and is included in CISA's Known Exploited Vulnerabilities (KEV) catalog, indicating confirmed real-world attacks.
System administrators should apply the latest Linux Kernel updates to mitigate this memory management flaw and prevent potential denial-of-service or privilege escalation.
Technical Analysis
CVE-2021-22600 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
CISA has added CVE-2021-22600 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.
Affected Vendors & Products
Exploit & PoC Resources
All References (1)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-22600 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
- !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
- !Active exploitation confirmed — treat as P1