CVE-2026-48108: Eugeny Russh

Medium severity, CVSS 5.3. EPSS: 0.5% chance of exploitation in the next 30 days.

Russh is a Rust SSH client & server library. From version 0.34.0-beta.1 to before version 0.61.0, russh did not enforce the SSH identification-string rules as deliberately as OpenSSH. In particular, the server-side identification reader used the same permissive path as the client, allowing pre-banner lines from clients, and the reader did not enforce a bounded number of pre-banner lines. For a library server built on russh, this could allow a remote peer to hold connection setup resources in the cleartext pre-authentication phase with malformed identification input that should have been rejected early. This issue has been patched in version 0.61.0.

Affected products

• Eugeny Russh: from 0.34.0-beta.1, before 0.61.0 (fixed in 0.61.0)

Published 2026-06-10. Last modified 2026-07-23.