CVE-2026-44214

Description

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.

PUBLISHED Reserved 2026-05-05 | Published 2026-05-26 | Updated 2026-05-27 | Assigner GitHub_M

Problem types

CWE-93: Improper Neutralization of CRLF Sequences ('CRLF Injection')

CWE-113: Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')

Product status

References

github.com/...ncoder/security/advisories/GHSA-m9g3-3g99-mhpx exploit

github.com/...ncoder/security/advisories/GHSA-m9g3-3g99-mhpx

cve.org (CVE-2026-44214)

nvd.nist.gov (CVE-2026-44214)

Download JSON