{"action":"Upgrade engine.io to 6.6.10 or later.","affected":[{"fixed":"6.6.10","introduced":"6.6.0"}],"component":"engine.io","cve_ids":["CVE-2026-102599"],"ecosystem":"npm","epss":0.00576,"exploited":false,"fixed_versions":["6.6.10"],"ghsa_id":"GHSA-2gc4-cqfq-p2gv","id":"tcs_01M5KET164TX2JJ7SG8GCW7NQQ","modified_at":"2026-09-30T00:00:03.845828732Z","published_at":"2026-09-29T23:44:33Z","references":["https://osv.dev/vulnerability/GHSA-2gc4-cqfq-p2gv","https://github.com/socketio/socket.io/security/advisories/GHSA-2gc4-cqfq-p2gv","https://github.com/socketio/socket.io/commit/86db1fc3db2cd315a065d64c4e48918ccf9b4729","https://github.com/socketio/socket.io","https://github.com/socketio/socket.io/releases/tag/engine.io@6.6.10"],"severity":{"label":"high","score":7.5},"sources":[{"source":"osv","source_id":"GHSA-2gc4-cqfq-p2gv","url":"https://osv.dev/vulnerability/GHSA-2gc4-cqfq-p2gv"}],"summary":"Socket.IO: Engine.IO Protocol Revision Mismatch DoS"}