Back

MEDIUM

russh server userauth state is not reset when authentication principal changes

Published Jun 10, 2026

Description

Russh is a Rust SSH client & server library. From version 0.34.0-beta.1 to before version 0.61.0, the russh server authentication path keeps internal userauth state across SSH_MSG_USERAUTH_REQUEST messages without separating that state when the request principal changes. RFC 4252 allows the user name and service name fields to change between authentication requests. The issue is not that such changes are invalid. The issue is that russh-owned authentication state, such as remaining methods, partial-success state, and in-progress method state, can remain associated with the connection and then influence a later request for a different (user, service). This is an internal library state mismatch. This issue has been patched in version 0.61.0.

Affected products

Remediation

No remediation recorded yet.

References (4)

Change history (0)

No recorded changes yet.

Sources
CVE.org / MITRE
Status PUBLISHED
Assigner GitHub_M
Published Jun 10, 2026
Updated Jun 11, 2026
Reserved May 15, 2026
CISA Vulnrichment
Updated Jun 11, 2026
NVD
Status Deferred
Modified Jul 23, 2026
Red Hat
Severity n/a
Public date n/a
ENISA EUVD
Assigner GitHub_M
Published Jun 10, 2026
Updated Jun 11, 2026
Exploited since n/a
EUVD-2026-36126 GHSA-HPV4-5H6F-WQR3