CVE-2026-102825: Russh: Configured server auth-attempt cap is not enforced in the USERAUTH_REQUEST runtime path

CVE-2026-102825 · Severity: low · CVSS 3.7 · Published 2026-09-29

Russh is a Rust SSH client and server library. Prior to 0.62.6, the USERAUTH_REQUEST path reached from server::run_stream in russh/src/server/encrypted.rs increments self.common.auth_attempts but never compares it with server::Config.max_auth_attempts. An unauthenticated remote client can continue submitting authentication requests on one connection beyond the configured cap, bypassing the deployment's attempt-limiting policy and increasing online guessing opportunity and backend authentication workload. This issue is fixed in version 0.62.6.

Technologies: russh (crates.io). Vendors: crates.io.

Quick answers

Is CVE-2026-102825 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-102825 being exploited in the wild.
How severe is CVE-2026-102825?
Low severity, with a CVSS score of 3.7, published 29 September 2026.
Which products and versions are affected?
russh (crates.io) <= 0.62.5, SEMVER:introduced=0,fixed=0.62.6.
Is there a fix for CVE-2026-102825?
Yes. russh (crates.io): upgrade to 0.62.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2026-102825?
Check whether you run russh (crates.io) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • russh (crates.io): upgrade to 0.62.6 or later
    cargo update -p russh

Affected products

  • russh (crates.io) <= 0.62.5, SEMVER:introduced=0,fixed=0.62.6

Identifiers

  • CVE-2026-102825
  • GHSA-g6xm-f9xp-qq35

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