CVE-2026-44214 MEDIUM

CVE-2026-44214: eventsource-encoder: SSE event injection via unsanitized event and id fields

Vendor Rexxars
Product eventsource-encoder
Weakness CWE-93 · CRLF injection
Published May 26, 2026
Last update May 27, 2026
View on NVD All CVEs

CVSS base score

5.8/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity Low

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

May 26, 2026 CVE published
May 27, 2026 Record updated