{"cve":"CVE-2026-102821","nvd":{"published":"2026-09-29T19:17:23.993","modified":"2026-09-30T20:17:23.793","status":"Deferred","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. This issue is fixed in version 0.63.2.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":6.5},"cwes":["CWE-400","CWE-770"],"references":["https://github.com/Eugeny/russh/commit/a282af361ac99bc76b80876d1aae128e89dbf66b","https://github.com/Eugeny/russh/releases/tag/v0.63.2","https://github.com/Eugeny/russh/security/advisories/GHSA-35g8-35p8-c8fw","https://github.com/Eugeny/russh/security/advisories/GHSA-35g8-35p8-c8fw"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:56:48.555445741+00:00"},"epss":{"cve":"CVE-2026-102821","score":0.00358,"percentile":0.29286,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-35g8-35p8-c8fw","url":"https://osv.dev/vulnerability/GHSA-35g8-35p8-c8fw","summary":"Russh: Unbounded memory exhaustion via CHANNEL_OPEN flood during a client-stalled rekey","modified":"2026-10-01T00:00:04.683452538Z","packages":[{"ecosystem":"crates.io","name":"russh","purl":"pkg:cargo/russh","ranges":["<0.63.2"],"fixed":["0.63.2"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}