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 KEXECDHREPLY containing a server ephemeral value that is not 32 bytes long. The client-side Curve25519Kex::computesharedsecret function in russh/src/kex/curve25519.rs passes the decoded exchange.serverephemeral value to clonefrom_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.
{
"cwe_ids": [
"CWE-704",
"CWE-754"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/73xxx/CVE-2026-73429.json",
"cna_assigner": "GitHub_M"
}