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.
A local attacker, with a low-privilege account, can achieve full data confidentiality loss, arbitrary modification of data, complete denial of service or system unavailability. Federal agencies are required to remediate by 2022-07-18 under CISA BOD 22-01.
This is a Out-of-bounds Write (CWE-787) vulnerability in Red Hat Polkit. 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. Exploitation requires local access, low attack complexity, a low-privilege authenticated account, and no user interaction required.
Probably yes if any of these apply:
Active exploitation documented in the wild. Threat-research write-up: http://packetstormsecurity.com/files/166196/Polkit-pkexec-Local-Privilege-Escalation.html
Manual remediation steps
Apply the Vendor Patch
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog — apply the vendor's security update as soon as possible.
CISA required action: Apply updates per vendor instructions.
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