CVE-2026-35515

Nest is a framework for building scalable Node.js server-side applications. Prior to 11.1.18, SseStream._transform() interpolates message.type and message.id directly into Server-Sent Events text protocol output without sanitizing newline characters (\r, \n). Since the SSE protocol treats both \r and \n as field delimiters and \n\n as event boundaries, an attacker who can influence these fields through upstream data sources can inject arbitrary SSE events, spoof event types, and corrupt reconnection state. This vulnerability is fixed in 11.1.18.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact LOW

Scope CHANGED

References

Link	Resource
https://github.com/nestjs/nest/security/advisories/GHSA-36xv-jgw5-4q75	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nestjs:nest:*:*:*:*:*:node.js:*:*

History

17 Apr 2026, 20:36

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 6.1
References	~~() https://github.com/nestjs/nest/security/advisories/GHSA-36xv-jgw5-4q75 -~~	() https://github.com/nestjs/nest/security/advisories/GHSA-36xv-jgw5-4q75 - Vendor Advisory
First Time		Nestjs Nestjs nest
CPE		cpe:2.3:a:nestjs:nest::::::node.js::*

07 Apr 2026, 16:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-07 16:16

Updated : 2026-04-17 20:36

NVD link : CVE-2026-35515

Mitre link : CVE-2026-35515

CVE.ORG link : CVE-2026-35515

JSON object : View

Products Affected

nestjs

nest

CWE

CWE-74

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

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