CVE-2026-44214
Medium
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.
SeverityMedium
CVSS5.8
Exploit probability—
ProductRexxars Eventsource-encoder
PublishedMay 26, 2026
First seenMay 26, 2026
Weakness typeCWE-93CWE-93CWE-113CWE-113
How to fix
Update
- rexxars eventsource-encoder1.0.2 or later
- eventsource-encoder1.0.2 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| rexxars eventsource-encoder | v < 1.0.2 | 1.0.2 |
| eventsource-encodernpm | v < 1.0.2 | 1.0.2 |
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