{"schemaVersion":3,"id":"CVE-2026-102821","aliases":["CGA-mhgm-c968-4vx4","CGA-w82w-fmgv-7cw8","GHSA-35g8-35p8-c8fw","DEBIAN-CVE-2026-102821","UBUNTU-CVE-2026-102821"],"status":"published","duplicateOf":null,"title":null,"description":"Russh is a Rust SSH client and server library. Prior to 0.63.2, an authenticated remote peer can send SSH_MSG_KEXINIT without the required SSH_MSG_KEX_ECDH_INIT and then flood SSH_MSG_CHANNEL_OPEN messages while SessionKexState::InProgress prevents priority_receiver in russh/src/server/session.rs from being drained. The server continues processing network input and enqueues a ChannelOpenReply for each request on an unbounded channel, allowing one connection to grow memory until the process is terminated. 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