CVE-2026-42189: CWE-770: Allocation of Resources Without Limits or Throttling in Eugeny russh
Russh is a Rust SSH client & server library. Prior to version 0.60.1, a pre-authentication denial-of-service vulnerability exists in the server's keyboard-interactive authentication handler. A malicious client can crash any russh-based server that implements keyboard-interactive auth (e.g., for 2FA/TOTP) with a single malformed packet, requiring no credentials. This issue has been patched in version 0.60.1.
AI Analysis
Technical Summary
The vulnerability CVE-2026-42189 affects russh versions before 0.60.1 and is categorized under CWE-770 (Allocation of Resources Without Limits or Throttling) and CWE-789 (Uncontrolled Memory Allocation). It allows an unauthenticated attacker to cause a denial-of-service by crashing the server during the keyboard-interactive authentication phase via a single malformed packet. The issue is resolved in russh version 0.60.1.
Potential Impact
Exploitation of this vulnerability results in a denial-of-service condition, causing the russh-based server to crash and become unavailable. There is no impact on confidentiality or integrity, only availability is affected. No credentials or prior authentication are required to trigger the crash.
Mitigation Recommendations
This vulnerability is fixed in russh version 0.60.1. Users of russh should upgrade to version 0.60.1 or later to remediate this issue. Patch status is not explicitly stated in the vendor advisory content, but the description confirms the fix is included in version 0.60.1. No additional mitigations are indicated.
CVE-2026-42189: CWE-770: Allocation of Resources Without Limits or Throttling in Eugeny russh
Description
Russh is a Rust SSH client & server library. Prior to version 0.60.1, a pre-authentication denial-of-service vulnerability exists in the server's keyboard-interactive authentication handler. A malicious client can crash any russh-based server that implements keyboard-interactive auth (e.g., for 2FA/TOTP) with a single malformed packet, requiring no credentials. This issue has been patched in version 0.60.1.
CVSS v3.1
Score 7.5high
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-42189 affects russh versions before 0.60.1 and is categorized under CWE-770 (Allocation of Resources Without Limits or Throttling) and CWE-789 (Uncontrolled Memory Allocation). It allows an unauthenticated attacker to cause a denial-of-service by crashing the server during the keyboard-interactive authentication phase via a single malformed packet. The issue is resolved in russh version 0.60.1.
Potential Impact
Exploitation of this vulnerability results in a denial-of-service condition, causing the russh-based server to crash and become unavailable. There is no impact on confidentiality or integrity, only availability is affected. No credentials or prior authentication are required to trigger the crash.
Mitigation Recommendations
This vulnerability is fixed in russh version 0.60.1. Users of russh should upgrade to version 0.60.1 or later to remediate this issue. Patch status is not explicitly stated in the vendor advisory content, but the description confirms the fix is included in version 0.60.1. No additional mitigations are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-25T01:53:21.583Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69fe4242cbff5d8610241d75
Added to database: 05/08/2026, 20:06:26 UTC
Last enriched: 05/16/2026, 10:54:55 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 142
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