CVE-2026-35515

Description

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.

PUBLISHED Reserved 2026-04-03 | Published 2026-04-07 | Updated 2026-04-07 | Assigner GitHub_M

Problem types

CWE-74: Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

Product status

References

github.com/...s/nest/security/advisories/GHSA-36xv-jgw5-4q75

cve.org (CVE-2026-35515)

nvd.nist.gov (CVE-2026-35515)

Download JSON