CVE-2026-42189
Russh: Pre-auth DoS via unbounded allocation in keyboard-interactive auth
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.
INFO
Published Date :
May 8, 2026, 8:16 p.m.
Last Modified :
May 14, 2026, 6:07 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-42189
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update russh to version 0.60.1.
- Disable keyboard-interactive authentication if updating is not possible.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-42189.
| URL | Resource |
|---|---|
| https://github.com/Eugeny/russh/commit/6c3c80a9b6d60763d6227d60fa8310e57172a4d1 | Patch |
| https://github.com/Eugeny/russh/releases/tag/v0.60.1 | Product Release Notes |
| https://github.com/Eugeny/russh/security/advisories/GHSA-f5v4-2wr6-hqmg | Exploit Mitigation Vendor Advisory |
| https://github.com/Eugeny/russh/security/advisories/GHSA-f5v4-2wr6-hqmg | Exploit Mitigation Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-42189 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-42189
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-42189 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-42189 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
May. 14, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:russh_project:russh:*:*:*:*:*:rust:*:* versions up to (excluding) 0.60.1 *cpe:2.3:a:warpgate_project:warpgate:*:*:*:*:*:*:*:* versions up to (excluding) 0.23.1 Added Reference Type GitHub, Inc.: https://github.com/Eugeny/russh/commit/6c3c80a9b6d60763d6227d60fa8310e57172a4d1 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/Eugeny/russh/releases/tag/v0.60.1 Types: Product, Release Notes Added Reference Type CISA-ADP: https://github.com/Eugeny/russh/security/advisories/GHSA-f5v4-2wr6-hqmg Types: Exploit, Mitigation, Vendor Advisory Added Reference Type GitHub, Inc.: https://github.com/Eugeny/russh/security/advisories/GHSA-f5v4-2wr6-hqmg Types: Exploit, Mitigation, Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
May. 11, 2026
Action Type Old Value New Value Added Reference https://github.com/Eugeny/russh/security/advisories/GHSA-f5v4-2wr6-hqmg -
New CVE Received by [email protected]
May. 08, 2026
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-770 Added CWE CWE-789 Added Reference https://github.com/Eugeny/russh/commit/6c3c80a9b6d60763d6227d60fa8310e57172a4d1 Added Reference https://github.com/Eugeny/russh/releases/tag/v0.60.1 Added Reference https://github.com/Eugeny/russh/security/advisories/GHSA-f5v4-2wr6-hqmg