CVE-2026-111062 Details
Description
russh is a Rust SSH client and server library. From version 0.34.0-beta.1 until version 0.64.0, its SSH server does not require the signature algorithm in a public-key authentication signature to match the algorithm named in the authentication request. A client possessing an authorized RSA private key can announce rsa-sha2-512 while supplying a valid ssh-rsa SHA-1 signature, bypassing restrictions or producing misleading audit records when applications rely on the requested algorithm. A valid private-key signature remains required, and russh clients are not affected. This issue is fixed in version 0.64.0.
A vulnerability exists in the russh SSH client and server library, specifically in versions 0.34.0-beta.1 prior to 0.64.0. The issue arises in the SSH server's public-key authentication process, where the library fails to ensure that the signature algorithm used in a public-key authentication signature matches the algorithm specified in the authentication request. This flaw allows a client with an authorized RSA private key to manipulate the signature algorithm being used, potentially bypassing application restrictions or creating inaccurate audit records. The vulnerability is rooted in the server's authentication handling, which does not compare the requested and actual signature algorithms, leading to possible acceptance of weaker signature types.
Users should update to russh version 0.64.0 or later, where this vulnerability has been fixed.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Nov 5, 2026CISA-ADP
Assessed Nov 5, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/Eugeny/russh/security/advisories/GHSA-j7h2-66j4-ghjf | CISA-ADP | AdvisoryExploitRemedyVendor |
| https://github.com/Eugeny/russh/commit/a0ded76bdc352f8fbeaaeb175fb2a0c586fbc8f2 | [email protected] | Source CodeVendor |
| https://github.com/Eugeny/russh/pull/759 | [email protected] | Issue TrackingVendor |
| https://github.com/Eugeny/russh/releases/tag/v0.64.0 | [email protected] | Release NotesVendor |
| https://github.com/Eugeny/russh/security/advisories/GHSA-j7h2-66j4-ghjf | [email protected] | AdvisoryExploitRemedyVendor |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-347 | Improper Verification of Cryptographic Signature | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| Eugeny russh | >= 0.34.0-beta.1, < 0.64.0 (semver) |
CPE
Remediation
| |
Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Nov 5, 2026 | CVE Modified | CISA-ADP |
| Nov 5, 2026 | New CVE Received | [email protected] |