CVEvulnerability

CVE-2026-35515

6.3 MEDIUM Published 2026-04-07 Modified 2026-10-26 Official page ↗
Status
Analyzed
Published
2026-04-07
Last modified
2026-10-26
Assigner
[email protected]
CVSS 4.0 ([email protected])
6.3 MEDIUM — CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1 ([email protected])
6.1 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:L
Weaknesses
CWE-74

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.

Affected configurations

• nestjs nest (< 11.1.18)

Related

Weakness · CWE (1)

  • CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component weakness

References