CVE-2026-73429

Russh is a Rust SSH client & server library. Prior to 0.62.4, a malicious SSH server can crash a russh client session with a malformed KEX_ECDH_REPLY containing a server ephemeral value that is not 32 bytes long. The client-side Curve25519Kex::compute_shared_secret function in russh/src/kex/curve25519.rs passes the decoded exchange.server_ephemeral value to clone_from_slice without validating its length, causing a deterministic panic before the server host key is verified. The panic terminates the spawned client session task and surfaces as a JoinError, while the embedding process normally remains running. This issue is fixed in version 0.62.4.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/Eugeny/russh/commit/a7fc1eb5717264e31c3c5f7dd849b73989a08f3d
https://github.com/Eugeny/russh/releases/tag/v0.62.4
https://github.com/Eugeny/russh/security/advisories/GHSA-g9hv-x236-4qp3
https://github.com/Eugeny/russh/security/advisories/GHSA-g9hv-x236-4qp3

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-12 21:17

Updated : 2026-09-09 21:02

NVD link : CVE-2026-73429

Mitre link : CVE-2026-73429

CVE.ORG link : CVE-2026-73429

JSON object : View

Products Affected

No product.

CWE

CWE-704

Incorrect Type Conversion or Cast

CWE-754

Improper Check for Unusual or Exceptional Conditions

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