CVE-2026-44214

eventsource-encoder encodes events as well-formed EventSource/Server Sent Event (SSE) messages. Prior to 1.0.2, eventsource-encoder does not sanitize the event or id fields of an EventSourceMessage before serializing them. An attacker who controls either field can inject arbitrary Server-Sent Events line terminators (n, r, or rn) and thereby forge additional SSE fields or entire messages on the stream. This vulnerability is fixed in 1.0.2.

More information : https://github.com/rexxars/eventsource-encoder/security/advisories/GHSA-m9g3-3g99-mhpx