Answer in brief
CVE-2026-73430 records a Medium severity (CVSS 5.3) vulnerability in Russh: Pre-auth remote panic via all-zero Curve25519 peer public value (encode_mpint OOB). The current sources do not mark it as known exploited. The current feed maps russh (crates.io), Eugeny/russh (generic), russh (rust). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps russh (crates.io), Eugeny/russh (generic), russh (rust). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| russhcrates.io | >=0 <0.62.4 | 0.62.4 |
| Eugeny/russhgeneric | < 0.62.4 | Not reported |
| russhrust | <=0.62.3 | 0.62.4 |
Published upstream
Aug 12, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 12, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 12, 2026
Russh is a Rust SSH client & server library. Prior to 0.62.4, an unauthenticated SSH client can cause a denial of service by sending SSH_MSG_KEX_ECDH_INIT with a 32-byte all-zero Q_C value. Curve25519Kex::server_dh in russh/src/kex/curve25519.rs accepts the all-zero peer public value and computes an all-zero shared secret, after which compute_exchange_hash calls encode_mpint in russh/src/kex/mod.rs and indexes beyond the end of the input while skipping leading zero bytes. The resulting panic occurs before authentication and terminates the server key-exchange task. This issue is fixed in version 0.62.4.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-73430 records a Medium severity (CVSS 5.3) vulnerability in Russh: Pre-auth remote panic via all-zero Curve25519 peer public value (encode_mpint OOB). The current sources do not mark it as known exploited. The current feed maps russh (crates.io), Eugeny/russh (generic), russh (rust). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps russh (crates.io), Eugeny/russh (generic), russh (rust). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| russhcrates.io | >=0 <0.62.4 | 0.62.4 |
| Eugeny/russhgeneric | < 0.62.4 | Not reported |
| russhrust | <=0.62.3 | 0.62.4 |
Published upstream
Aug 12, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 12, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 12, 2026
Russh is a Rust SSH client & server library. Prior to 0.62.4, an unauthenticated SSH client can cause a denial of service by sending SSH_MSG_KEX_ECDH_INIT with a 32-byte all-zero Q_C value. Curve25519Kex::server_dh in russh/src/kex/curve25519.rs accepts the all-zero peer public value and computes an all-zero shared secret, after which compute_exchange_hash calls encode_mpint in russh/src/kex/mod.rs and indexes beyond the end of the input while skipping leading zero bytes. The resulting panic occurs before authentication and terminates the server key-exchange task. This issue is fixed in version 0.62.4.
Quoted source text, attributed separately from HOL analysis.