High 7.5Published May 8, 2026

CVE-2026-42189Russh: Pre-auth DoS via unbounded allocation in keyboard-interactive auth

Updated under an hour ago (Oct 28, 2026, 3:23 AM ET)

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It affects Eugeny russh and 2 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Eugeny russh

Exploited in the last 30 days

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: 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-770, CWE-789
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: May 11, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Eugeny russh eugeny:russh (from the name)	before 0.60.1	CNA record
russh_project russh russh_project:russh	before 0.60.1	NVD
warpgate_project warpgate warpgate_project:warpgate	before 0.23.1	NVD

References

References

https://github.com/Eugeny/russh/security/advisories/GHSA-f5v4-2wr6-hqmg	x-refsource-confirm, exploit, mitigation, vendor-advisory
https://github.com/Eugeny/russh/commit/6c3c80a9b6d60763d6227d60fa8310e57172a4d1	x-refsource-misc, patch
https://github.com/Eugeny/russh/releases/tag/v0.60.1	x-refsource-misc, product, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.