Arch Linux ASA-202103-6 Medium: OpenSSH Arbitrary Code Threat

Arch Linux Security Advisory ASA-202103-6
========================================
Severity: Medium
Date    : 2021-03-13
CVE-ID  : CVE-2021-28041
Package : openssh
Type    : arbitrary code execution
Remote  : Yes
Link    : https://security.archlinux.org/AVG-1657

Summary
======
The package openssh before version 8.5p1-1 is vulnerable to arbitrary
code execution.

Resolution
=========
Upgrade to 8.5p1-1.

# pacman -Syu "openssh>=8.5p1-1"

The problem has been fixed upstream in version 8.5p1.

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

Description
==========
ssh-agent in OpenSSH before 8.5 has a double free that may be relevant
in a few less-common scenarios, such as unconstrained agent-socket
access on a legacy operating system, or the forwarding of an agent to
an attacker-controlled host.

Impact
=====
A remote attacker with enough privileges to access the socket of the
forwarding agent might be able to execute arbitrary code.

References
=========
https://www.openssh.org/security.html
https://www.openssh.org/txt/release-8.5
https://github.com/openssh/openssh-portable/commit/e04fd6dde16de1cdc5a4d9946397ff60d96568db
https://security.archlinux.org/CVE-2021-28041