{"api_version":"1","generated_at":"2026-09-29T22:36:14+00:00","cve":"CVE-2026-102821","urls":{"html":"https://cve.report/CVE-2026-102821","api":"https://cve.report/api/cve/CVE-2026-102821.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-102821","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-102821"},"summary":{"title":"Russh: Unbounded memory exhaustion via CHANNEL_OPEN flood during a client-stalled rekey","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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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. This issue is fixed in version 0.63.2.","Type":"Description","Title":"Russh: Unbounded memory exhaustion via CHANNEL_OPEN flood during"}]}}}