HIGH CISA KEV

CVE-2021-4034

CVSS v3

7.8

HIGH

EPSS Score

87.3%

exploit probability

CISA KEV

Yes

known exploited

Exploitation

SSVC status

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.

CISA Known Exploited Vulnerability

Date Added
6/27/2022
Patch Due Date
7/18/2022
Ransomware Use
Unknown

Technical details

Published
1/28/2022

Frequently asked questions

What is CVE-2021-4034?

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.

Is CVE-2021-4034 actively exploited?

Yes. CVE-2021-4034 is on the CISA Known Exploited Vulnerabilities (KEV) catalog, meaning it has been confirmed as actively exploited in the wild. CISA requires federal agencies to patch by 7/18/2022.

What is the CVSS score for CVE-2021-4034?

CVE-2021-4034 has a CVSS v3 base score of 7.8 (HIGH severity).

Is CVE-2021-4034 affecting your environment?

Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.