Russh is a Rust SSH client and server library. Prior to 0.63.0, the hybrid ML-KEM 768 and X25519 implementation in russh/src/kex/hybrid_mlkem.rs accepts an all-zero 32-byte peer X25519 public key in both server_dh and compute_shared_secret, forcing the X25519 contribution to the combined shared secret to zero. A malicious SSH peer can therefore make the combined secret depend only on ML-KEM, defeating the hybrid exchange's intended fallback protection if ML-KEM is later weakened. This issue is fixed in version 0.63.0.
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Affected Vendors & Products
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History
Wed, 30 Sep 2026 21:30:00 +0000
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ssvc
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Wed, 30 Sep 2026 00:15:00 +0000
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| Weaknesses | CWE-358 | |
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threat_severity
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threat_severity
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Tue, 29 Sep 2026 21:45:00 +0000
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Eugeny
Eugeny russh |
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Eugeny
Eugeny russh |
Tue, 29 Sep 2026 18:30:00 +0000
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| Description | Russh is a Rust SSH client and server library. Prior to 0.63.0, the hybrid ML-KEM 768 and X25519 implementation in russh/src/kex/hybrid_mlkem.rs accepts an all-zero 32-byte peer X25519 public key in both server_dh and compute_shared_secret, forcing the X25519 contribution to the combined shared secret to zero. A malicious SSH peer can therefore make the combined secret depend only on ML-KEM, defeating the hybrid exchange's intended fallback protection if ML-KEM is later weakened. This issue is fixed in version 0.63.0. | |
| Title | Russh: Missing X25519 zero-point validation in hybrid ML-KEM key exchange | |
| Weaknesses | CWE-327 | |
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cvssV3_1
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Status: PUBLISHED
Assigner: GitHub_M
Published: 2026-09-29T18:27:41.650Z
Updated: 2026-09-30T20:24:58.381Z
Reserved: 2026-09-29T17:25:25.265Z
Link: CVE-2026-102824
Updated: 2026-09-30T20:09:35.101Z
Status : Deferred
Published: 2026-09-29T19:17:24.543
Modified: 2026-09-30T21:17:05.920
Link: CVE-2026-102824