A russh SSH server accepts a publickey authentication whose signature uses a different algorithm than the one named in the request

影響: rust:russh >= 0.34.0-beta.1, < 0.64.0 → 0.64.0

In russh/src/server/encrypted.rs, server_read_auth_request_pk (0.63.3, around lines 880-990): The requested algorithm name (pubkey_algo) is read and only used to decode the key: PublicKeyOrCertificate::decode(&pubkey_algo, &pubkey_key). The derived hash_alg is then dropped (PublicKeyOrCertificate::PublicKey { ref key, .. }). The signature blob is decoded (Signature::decode) and verified with Verifier::verify(&pubkey, &buf, &sig). ssh-key picks the hash from the signature's own algorithm…

在 GitHub Advisory Database 阅读

2026/10/20 02:06，GitHub Advisory Database 发布了“A russh SSH server accepts a publickey authentication whose signature uses a different algorithm than the one named in the request”（类型：漏洞公告）。严重程度为“低危”（low）。相关技术：Rust。CVE：CVE-2026-111062。