CVE-2026-44214 — eventsource-encoder: SSE event injection via unsanitized event and id fields
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 a…
Published: 2026-05-26 · CVSS: 5.8 · CVSS 3.1
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 \r\n) and thereby forge additional SSE fields or entire messages on the stream. This vulnerability is fixed in 1.0.2.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7