CVE-2026-44214
eventsource-encoder: SSE event injection via unsanitized event and id fields
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.
INFO
Published Date :
May 26, 2026, 8:16 p.m.
Last Modified :
May 28, 2026, 2:30 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update eventsource-encoder to version 1.0.2.
- Ensure event and id fields are sanitized.
- Avoid user-controlled input in event/id fields.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-44214.
| URL | Resource |
|---|---|
| https://github.com/rexxars/eventsource-encoder/security/advisories/GHSA-m9g3-3g99-mhpx | Exploit Mitigation Vendor Advisory |
| https://github.com/rexxars/eventsource-encoder/security/advisories/GHSA-m9g3-3g99-mhpx | Exploit Mitigation Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-44214 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-44214
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-44214 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-44214 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
May. 28, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N Added CPE Configuration OR *cpe:2.3:a:rexxars:eventsource-encoder:*:*:*:*:*:node.js:*:* versions up to (excluding) 1.0.2 Added Reference Type CISA-ADP: https://github.com/rexxars/eventsource-encoder/security/advisories/GHSA-m9g3-3g99-mhpx Types: Exploit, Mitigation, Vendor Advisory Added Reference Type GitHub, Inc.: https://github.com/rexxars/eventsource-encoder/security/advisories/GHSA-m9g3-3g99-mhpx Types: Exploit, Mitigation, Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
May. 27, 2026
Action Type Old Value New Value Added Reference https://github.com/rexxars/eventsource-encoder/security/advisories/GHSA-m9g3-3g99-mhpx -
New CVE Received by [email protected]
May. 26, 2026
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N Added CWE CWE-93 Added CWE CWE-113 Added Reference https://github.com/rexxars/eventsource-encoder/security/advisories/GHSA-m9g3-3g99-mhpx