MFH: r543704

archivers/ark: security fix

KDE Project Security Advisory

Title: Ark: maliciously crafted archive can install files outside the extraction directory.
Risk Rating: Important
CVE: CVE-2020-16116
Versions: ark <= 20.04.3
Author: Elvis Angelaccio <elvis.angelaccio@kde.org>
Date: 30 July 2020

Overview

A maliciously crafted archive with "../" in the file paths
would install files anywhere in the user's home directory upon extraction.

Proof of concept

For testing, an example of malicious archive can be found at
https://github.com/jwilk/traversal-archives/releases/download/0/relative2.zip

Impact

Users can unwillingly install files like a modified .bashrc, or a malicious
script placed in ~/.config/autostart

Workaround

Users should not use the 'Extract' context menu from the Dolphin file manager.
Before extracting a downloaded archive using the Ark GUI, users should inspect it
to make sure it doesn't contain entries with "../" in the file path.

Solution

Ark 20.08.0 prevents loading of malicious archives and shows a warning message
to the users.

Alternatively,
https://invent.kde.org/utilities/ark/-/commit/0df592524fed305d6fbe74ddf8a196bc9ffdb92f
can be applied to previous releases.

Credits

Thanks to Dominik Penner for finding and reporting this issue and thanks to
Elvis Angelaccio and Albert Astals Cid for fixing it.

Approved by: ports-secteam (blanket)