Actively exploited in the wild
Red Hat Polkit Out-of-Bounds Read and Write Vulnerability
Red Hat - Polkit · Listed in the CISA KEV since 2022-06-27. This indicates confirmed attacks in production environments.
Required action: Apply updates per vendor instructions.
CVE-2021-4034
HighCVSS 7.8KEVExploitation Probability (EPSS)
Very high risk100th percentile - higher than 100% of all known CVEs
Summary
A local privilege escalation vulnerability was found in polkit's pkexec utility. pkexec doesn't handle the calling parameters count correctly and ends trying to execute environment variables as commands.
Risk Assessment
An unprivileged user can gain administrative rights on the machine, leading to full system compromise.
Recommendation
Update polkit to a patched version (e.g., 0.120-6 or later).
Original NVD description (English source)
A local privilege escalation vulnerability was found on polkit's pkexec utility. The pkexec application is a setuid tool designed to allow unprivileged users to run commands as privileged users according predefined policies. The current version of pkexec doesn't handle the calling parameters count correctly and ends trying to execute environment variables as commands. An attacker can leverage this by crafting environment variables in such a way it'll induce pkexec to execute arbitrary code. When successfully executed the attack can cause a local privilege escalation given unprivileged users administrative rights on the target machine.