Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') Affecting @nestjs/core package, versions <11.1.18
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Test your applications- Snyk IDSNYK-JS-NESTJSCORE-15920868
- published7 Apr 2026
- disclosed6 Apr 2026
- creditLê Minh Quân
Introduced: 6 Apr 2026
NewCVE-2026-35515 (opens in a new tab)How to fix?
Upgrade @nestjs/core to version 11.1.18 or higher.
Overview
@nestjs/core is a Nest - modern, fast, powerful node.js web framework (@core)
Affected versions of this package are vulnerable to Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') via the SseStream._transform function. An attacker can inject arbitrary Server-Sent Events, spoof event types, and corrupt reconnection state by supplying specially crafted newline characters in upstream data that is mapped to the type or id fields.
Note:
This is only exploitable if user-influenced data is mapped to these fields by developer code.