{"id":"GHSA-84hm-wfh8-c5pg","revision":"867718ef545e480aafa07c946a89536a","records":[{"revision":"867718ef545e480aafa07c946a89536a","observedAt":"2026-10-24T13:17:17.793+00:00","statement":{"source":"osv","id":"GHSA-84hm-wfh8-c5pg","aliases":["CVE-2026-44217"],"title":"sse-channel: SSE Injection via unsanitized event fields","description":"### Impact\n\nImplementations that allows user-provided values to be passed to `event`, `retry` or `id` fields would be susceptible to event spoofing, where an attacker could inject arbitrary messages into the stream.\n\n- **Event Spoofing:** Attacker can inject arbitrary SSE events into the stream\n- **Client-side Manipulation:** Injected events can trigger unintended behavior in frontend JavaScript EventSource listeners\n- **Data Integrity:** Consumers of the SSE stream cannot distinguish injected events from legitimate ones\n\n### Patches\nPatch available in v4.0.1.\n\n### Workarounds\nDo not allow user data to control `event`, `retry` or `id` fields, and if you must - sanitize the input before passing it to `sse-channel`, stripping any newlines. \n\n### Resources\n\nhttps://github.com/rexxars/sse-channel/issues/42","state":0,"publishedAt":"2026-05-05T22:17:02+00:00","modifiedAt":"2026-05-13T16:46:23.718132+00:00","affected":[{"ecosystem":"npm","name":"sse-channel","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"fixed","version":"4.0.1"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V4","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"MODERATE"}],"references":["https://github.com/rexxars/sse-channel/security/advisories/GHSA-84hm-wfh8-c5pg","https://nvd.nist.gov/vuln/detail/CVE-2026-44217","https://github.com/rexxars/sse-channel/issues/42","https://github.com/rexxars/sse-channel"],"sourceUrl":"https://github.com/advisories/GHSA-84hm-wfh8-c5pg","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-84hm-wfh8-c5pg","identifiers":["GHSA-84hm-wfh8-c5pg","CVE-2026-44217"]},"retained":false,"historicalAffected":[]}],"coverage":[]}