CVE-2021-4034 Information

Description

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.

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Reference

https://www.qualys.com/2022/01/25/cve-2021-4034/pwnkit.txt https://access.redhat.com/security/vulnerabilities/RHSB-2022-001 https://bugzilla.redhat.com/show_bug.cgi?id=2025869 https://gitlab.freedesktop.org/polkit/polkit/-/commit/a2bf5c9c83b6ae46cbd5c779d3055bff81ded683 http://packetstormsecurity.com/files/166196/Polkit-pkexec-Local-Privilege-Escalation.html http://packetstormsecurity.com/files/166200/Polkit-pkexec-Privilege-Escalation.html https://www.suse.com/support/kb/doc/?id=000020564 https://www.oracle.com/security-alerts/cpuapr2022.html

Attack Complexity

LOW

Privileges Required

LOW

User Interaction Required

LOW

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

7.8