CVE-2021-4034

Known Exploited Public Exploit

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.

Categories

7.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 88.73% Top 5%
KEV Since 
Vendor Advisory redhat.com
Affected: n/a polkit
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-4034?
CVE-2021-4034 has been scored as a high severity vulnerability.
How to fix CVE-2021-4034?
To fix CVE-2021-4034, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-4034 being actively exploited in the wild?
It is confirmed that CVE-2021-4034 is actively exploited. Be extra cautious if you are using vulnerable components. According to its EPSS score, there is a ~89% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-4034?
CVE-2021-4034 affects n/a polkit.
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