CVE-2021-4034

HIGH7.8

CISA KEV

Published 2022-01-28 · Updated 2026-08-15 · Source secalert@redhat.com

Summary

CVE-2021-4034 is a high-severity (CVSS 7.8) vulnerability in Red Hat Polkit. CISA added it to the Known Exploited Vulnerabilities catalog on June 27, 2022, which means exploitation in the wild has been confirmed; US federal agencies had to remediate it by July 18, 2022. CISA also lists it as known to be used in ransomware campaigns, so it should be prioritised accordingly. Red Hat has 9 vulnerabilities in the KEV catalog, 4 of them linked to ransomware.

All 9 known-exploited Red Hat vulnerabilities →

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

CWE-787CWE-125CWE-787

CISA Known-Exploited Vulnerability

Product: Red Hat — Polkit

Name: Red Hat Polkit Out-of-Bounds Read and Write Vulnerability

Date added: 2022-06-27 · Due: 2022-07-18

USED IN RANSOMWARE

Required action: Apply updates per vendor instructions.

References

View on NVD

More exploited Red Hat vulnerabilities

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JBoss RichFaces Framework — Red Hat JBoss RichFaces Framework Expression Language Injection Vulnerability
added 2023-09-28
CVE-2021-3560
Polkit — Red Hat Polkit Incorrect Authorization Vulnerability
added 2023-05-12
CVE-2010-1428
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added 2022-05-25
CVE-2010-0738
RANSOMWARE
JBoss — Red Hat JBoss Authentication Bypass Vulnerability
added 2022-05-25

View all →

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