CVE-2021-4034

Publication date 25 January 2022

Last updated 21 August 2024

Ubuntu priority

High

Why this priority?

Cvss 3 Severity Score

7.8 · High

Score breakdown

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.

Status

Package Ubuntu Release Status
policykit-1 22.04 LTS jammy
Fixed 0.105-31ubuntu1
21.10 impish
Fixed 0.105-31ubuntu0.1
21.04 hirsute Ignored end of life
20.04 LTS focal
Fixed 0.105-26ubuntu1.2
18.04 LTS bionic
Fixed 0.105-20ubuntu0.18.04.6
16.04 LTS xenial
14.04 LTS trusty

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Severity score breakdown

Parameter Value
Base score 7.8 · High
Attack vector Local
Attack complexity Low
Privileges required Low
User interaction None
Scope Unchanged
Confidentiality High
Integrity impact High
Availability impact High
Vector CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

References

Related Ubuntu Security Notices (USN)

    • USN-5252-1
    • PolicyKit vulnerability
    • 25 January 2022
    • USN-5252-2
    • PolicyKit vulnerability
    • 25 January 2022

Other references