# CVE-2026-48108: rust-russh: Russh is a Rust SSH client & server library

CVE-2026-48108 is fixed in rust-russh on 1 platform by DEBIAN-CVE-2026-48108 (version 0.64.1-1), released June 10, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-48108
- Priority: Routine
- CVSS: 5.3 (medium)
- EPSS: 0.0028
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- 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, 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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | rust-russh Debian 14 | 0.64.1-1 | [DEBIAN-CVE-2026-48108](https://patchblox.com/security/data/fix/linux/debian-cve-2026-48108.md) | Jun 10, 2026 |

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Data as of 2026-11-08T19:12:23Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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