CVE-2021-4034
Published: June 27, 2022
Official Description
The Red Hat polkit pkexec utility contains an out-of-bounds read and write vulnerability that allows for privilege escalation with administrative rights.
CISA KEV Advisory
Red Hat Polkit Out-of-Bounds Read and Write Vulnerability
The Red Hat polkit pkexec utility contains an out-of-bounds read and write vulnerability that allows for privilege escalation with administrative rights.
Apply updates per vendor instructions.
Risk Analysis
The Red Hat polkit pkexec utility contains an out-of-bounds read and write vulnerability that allows for privilege escalation to administrative rights. The very high EPSS score of 0.87261 indicates a significant likelihood of exploitation, and its inclusion in CISA's KEV confirms active exploitation, making this a critical local privilege escalation vulnerability.
This vulnerability is actively being exploited in the wild. While it is a local privilege escalation, its widespread impact makes it a significant threat.
Organizations should apply all available security updates for Red Hat systems to patch the polkit pkexec utility. Ensure systems are regularly updated and monitored for suspicious activity.
Technical Analysis
CVE-2021-4034 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-2021-4034 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-2021-4034 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