Polkit (formerly PolicyKit) is a component for controlling system-wide privileges in

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operating systems. It provides an organized way for non-privileged processes to communicate with privileged ones. Polkit allows a level of control of centralized system policy. It is developed and maintained by David Zeuthen from

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and hosted by the

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project. It is published as

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under the terms of version 2 of the

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. Since version 0.105, released in April 2012, the name of the project was changed from ''PolicyKit'' to ''polkit'' to emphasize that the system component was rewritten and that the

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had changed, breaking

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became the first

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to include PolicyKit, and it has since been used in other distributions, including

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since version 8.04 and

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since version 10.3. Some distributions, like Fedora, have already switched to the rewritten polkit. It is also possible to use polkit to execute commands with elevated privileges using the command ''pkexec'' followed by the command intended to be executed (with

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permission). However, it may be preferable to use

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, as this command provides more flexibility and security, in addition to being easier to configure.

Implementation

The polkitd

daemon Daimon or Daemon (Ancient Greek: , "god", "godlike", "power", "fate") originally referred to a lesser deity or guiding spirit such as the daimons of ancient Greek religion and mythology and of later Hellenistic religion and philosophy. The word ...

implements Polkit functionality.

Vulnerability

A memory corruption vulnerability PwnKit ( CVE-2021-4034) discovered in the ''pkexec'' command (installed on all major Linux distributions) was announced on January 25, 2022. The vulnerability dates back to the original distribution from 2009. The vulnerability received a CVSS score of 7.8 ("High severity") reflecting serious factors involved in a possible exploit: unprivileged users can gain full root privileges, regardless of the underlying machine architecture or whether the ''polkit'' daemon is running or not.

References

External links

polkit GitLab repository
at freedesktop.org
Documentation
at freedesktop.org
Why polkit
explaining polkit's role in a modern system Free software programmed in C Freedesktop.org Unix software {{Free-software-stub

Implementation

Vulnerability

See also

References

External links