CVE-2026-46705

The record

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 packages

Related vulnerabilities

• GHSA-hpv4-5h6f-wqr3 russh server userauth state is not reset when authentication principal changes Same vulnerability
• GHSA-4r3c-5hpg-58qr Russh SSH message fields were decoded through allocation-first parsers before… Also affects russh
• GHSA-76r6-x97p-67vr Russh: SSH identification parsing accepted non-canonical client banners and did not bound… Also affects russh
• GHSA-g9g7-5cgw-6v28 Russh: Unchecked keyboard-interactive prompt count in client auth path Also affects russh
• CVE-2026-48108 Russh is a Rust SSH client & server library. Also affects russh
• CVE-2026-48110 Russh is a Rust SSH client & server library. Also affects russh
• CVE-2026-46702 Russh is a Rust SSH client & server library. Also affects russh
• CVE-2026-46673 Russh is a Rust SSH client & server library. Also affects russh