Severity: High
Title: OpenSSH: Remote Code Execution
Date: July 01, 2024
Bugs: #935271
ID: 202407-09

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Synopsis
========

A vulnerability has been discovered in OpenSSH, which can lead to remote
code execution with root privileges.

Background
==========

OpenSSH is a free application suite consisting of server and clients
that replace tools like telnet, rlogin, rcp and ftp with more secure
versions offering additional functionality.

Affected packages
=================

Package Vulnerable Unaffected
---------------- ------------ ------------
net-misc/openssh < 9.7_p1-r6 >= 9.7_p1-r6

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

A vulnerability has been discovered in OpenSSH. Please review the CVE
identifier referenced below for details.

Impact
======

A critical vulnerability in sshd(8) was present in Portable OpenSSH
versions that may allow arbitrary code execution with root privileges.

Successful exploitation has been demonstrated on 32-bit Linux/glibc
systems with ASLR. Under lab conditions, the attack requires on
average 6-8 hours of continuous connections up to the maximum the
server will accept. Exploitation on 64-bit systems is believed to be
possible but has not been demonstrated at this time. It's likely that
these attacks will be improved upon.

Workaround
==========

There is no known workaround at this time.

Note that Gentoo has backported the fix to the following versions:

net-misc/openssh-9.6_p1-r5
net-misc/openssh-9.7_p1-r6

Resolution
==========

All OpenSSH users should upgrade to the latest version and restart the
sshd server (to ensure access for new sessions and no vulnerable code
keeps running).

# emerge --sync
# emerge --ask --oneshot --verbose ">=net-misc/openssh-9.7_p1-r6"

With OpenRC:
# rc-service sshd restart

With systemD:
# systemctl try-restart sshd.service

References
==========

[ 1 ] CVE-2024-6387
https://nvd.nist.gov/vuln/detail/CVE-2024-6387

Availability
============

This GLSA and any updates to it are available for viewing at
the Gentoo Security Website:

https://security.gentoo.org/glsa/202407-09

Concerns?
=========

Security is a primary focus of Gentoo Linux and ensuring the
confidentiality and security of our users' machines is of utmost
importance to us. Any security concerns should be addressed to
[email protected] or alternatively, you may file a bug at
https://bugs.gentoo.org.

License
=======

Copyright 2024 Gentoo Foundation, Inc; referenced text
belongs to its owner(s).

The contents of this document are licensed under the
Creative Commons - Attribution / Share Alike license.

https://creativecommons.org/licenses/by-sa/2.5