Subject: [ASA-202007-4] ffmpeg: arbitrary code execution

Arch Linux Security Advisory ASA-202007-4
=========================================

Severity: High
Date    : 2020-07-31
CVE-ID  : CVE-2020-13904
Package : ffmpeg
Type    : arbitrary code execution
Remote  : Yes
Link    : https://security.archlinux.org/AVG-1180

Summary
=======

The package ffmpeg before version 2:4.3.1-1 is vulnerable to arbitrary
code execution.

Resolution
==========

Upgrade to 2:4.3.1-1.

# pacman -Syu "ffmpeg>=2:4.3.1-1"

The problem has been fixed upstream in version 4.3.1.

Workaround
==========

None.

Description
===========

A use-after-free via a crafted EXTINF duration in an m3u8 file has been
found in ffmpeg <= 4.2.3, because parse_playlist in libavformat/hls.c
frees a pointer, and later that pointer is accessed in
av_probe_input_format3 in libavformat/format.c

Impact
======

An attacker can execute arbitrary code on the affected host via crafted
multimedia content.

References
==========

https://trac.ffmpeg.org/ticket/8673
https://patchwork.ffmpeg.org/project/ffmpeg/patch/20200529033905.41926-1-lq@chinaffmpeg.org/
https://security.archlinux.org/CVE-2020-13904