REDHAT-BUG-2401960: Medium severity OpenSSH OpenSSH vulnerability

Published Oct 6, 2025
·
Updated

ssh in OpenSSH before 10.1 allows control characters in usernames that originate from certain possibly untrusted sources, potentially leading to code execution when a ProxyCommand is used. The untrusted sources are the command line and %-sequence expansion of a configuration file. (A configuration file that provides a complete literal username is not categorized as an untrusted source.)

Affected Software

1 affected component
OpenSSH OpenSSH<10.1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade OpenSSH to a version that resolves this vulnerability.

    Fixed in 10.1
  2. Configuration

    When using ssh with ProxyCommand, ensure usernames cannot originate from untrusted command line inputs or %-sequence expansion of configuration files; avoid passing potentially attacker-controlled username strings to ssh.

    OpenSSH ssh ProxyCommand = use only trusted, non-untrusted-origin usernames (avoid untrusted sources that could inject control characters)

Event History

Oct 6, 2025
Data Sourced
via Red Hat·07:01 PM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of REDHAT-BUG-2401960?

The severity of REDHAT-BUG-2401960 is considered critical due to the potential for code execution.

2

How do I fix REDHAT-BUG-2401960?

To fix REDHAT-BUG-2401960, upgrade OpenSSH to version 10.1 or later where the vulnerability is addressed.

3

What vulnerability does REDHAT-BUG-2401960 describe?

REDHAT-BUG-2401960 describes a vulnerability in OpenSSH that allows control characters in usernames, which could lead to code execution.

4

Which versions of OpenSSH are affected by REDHAT-BUG-2401960?

OpenSSH versions prior to 10.1 are affected by REDHAT-BUG-2401960.

5

What components are involved in the vulnerability described by REDHAT-BUG-2401960?

The components involved include usernames derived from untrusted sources like command lines and configuration file expansions.

Contact

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