Arch Linux Security Advisory ASA-202004-6
========================================
Severity: Critical
Date    : 2020-04-04
CVE-ID  : CVE-2020-6819 CVE-2020-6820
Package : firefox
Type    : arbitrary code execution
Remote  : Yes
Link    : https://security.archlinux.org/AVG-1125

Summary
======
The package firefox before version 74.0.1-1 is vulnerable to arbitrary
code execution.

Resolution
=========
Upgrade to 74.0.1-1.

# pacman -Syu "firefox>=74.0.1-1"

The problems have been fixed upstream in version 74.0.1.

Workaround
=========
None.

Description
==========
- CVE-2020-6819 (arbitrary code execution)

A use-after-free vulnerability has been found in Firefox before 74.0.1
where under certain conditions, when running the nsDocShell destructor,
a race condition can cause a use-after-free. Mozilla is aware of
targeted attacks in the wild abusing this flaw.

- CVE-2020-6820 (arbitrary code execution)

A use-after-free vulnerability has been found in Firefox before 74.0.1
where, under certain conditions, when handling a ReadableStream, a race
condition can cause a use-after-free. Mozilla is aware of targeted
attacks in the wild abusing this flaw.

Impact
=====
A remote attacker can execute arbitrary code on the affected host.

References
=========
https://www.mozilla.org/en-US/security/advisories/mfsa2020-11/
https://www.mozilla.org/en-US/security/advisories/mfsa2020-11/#CVE-2020-6819
https://bugzilla.mozilla.org/show_bug.cgi?id=1620818
https://www.mozilla.org/en-US/security/advisories/mfsa2020-11/#CVE-2020-6820
https://bugzilla.mozilla.org/show_bug.cgi?id=1626728
https://security.archlinux.org/CVE-2020-6819
https://security.archlinux.org/CVE-2020-6820