CVE-2021-22600

Linux Kernel: Privilege Escalation

As of , CVE-2021-22600 in Linux Kernel is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch soon.

Exploited
Yes: CISA listed it on 11 April 2022
US federal deadline
2 May 202221 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Not known to CISA
EPSS score
0.07Higher than 93% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
EPSS when listed
0.01 on 11 April 2022EPSS on the day CISA listed it.
Public exploit
None foundNeither Metasploit nor Exploit-DB lists one.
Fix
No vendor link in CISA's entry

What CISA says to do

Apply updates per vendor instructions.

CISA's required action

What the flaw is

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's 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

The CVE record's description, from Google

CVE published
26 January 2022
Assigned by
Google
CVSS
6.6 Medium (CVSS 3.1, from the CNA)
CWE-415
Double Free
CISA SSVC, exploitation
active
CISA SSVC, automatable
no
CISA SSVC, technical impact
partial

Timeline

  1. The CVE record was published.
  2. CISA added it to its list of exploited vulnerabilities.
  3. The US federal deadline to fix it.

Kernel: other exploited entries

VulnerabilityProductOur groupListedDeadlineEPSS
CVE-2025-39682Improper Check for Unusual or Exceptional ConditionsLinux KernelPatch nowForensic triage required by CISA0.03
CVE-2025-39964Race ConditionLinux KernelPatch nowForensic triage required by CISA0.01
CVE-2026-53266Out-of-Bounds WriteLinux KernelPatch nowForensic triage required by CISA0.01
CVE-2026-53362UnspecifiedLinux KernelPatch nowForensic triage required by CISA0.01
CVE-2021-22555Heap Out-of-Bounds WriteLinux KernelPatch this weekMetasploit module; EPSS 0.79; verified Exploit-DB entry0.79
CVE-2013-6282Improper Input ValidationLinux KernelPatch this weekMetasploit module; verified Exploit-DB entry0.40
CVE-2019-13272Improper Privilege ManagementLinux KernelPatch this weekMetasploit module; EPSS 0.52; verified Exploit-DB entry0.52
CVE-2010-3904Improper Input ValidationLinux KernelPatch this weekMetasploit module; verified Exploit-DB entry0.16
CVE-2022-0847Privilege EscalationLinux KernelPatch this weekMetasploit module; EPSS 0.930.93
CVE-2021-3493Privilege EscalationLinux KernelPatch this weekMetasploit module0.49

All 31 entries for Kernel

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