CVE-2026-44214
MEDIUMeventsource-encoder: SSE event injection via unsanitized event and id fields
Title source: cnaDescription
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.
References (1)
Core 1
Core References
X_Refsource_Confirm x_refsource_confirm
https://github.com/rexxars/eventsource-encoder/security/advisories/GHSA-m9g3-3g99-mhpx
Scores
CVSS v3
5.8
EPSS
0.0026
EPSS Percentile
16.6%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-113
CWE-93
Status
published
Products (2)
npm/eventsource-encoder
0 - 1.0.2npm
rexxars/eventsource-encoder
< 1.0.2 (2 CPE variants)
Published
May 26, 2026
Tracked Since
May 27, 2026