SB2026040728 - Code injection in nestjs nest
Published: April 7, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Injection (CVE-ID: CVE-2026-35515)
The vulnerability allows a remote attacker to inject arbitrary SSE events, spoof event types, and corrupt reconnection state.
The vulnerability exists due to improper neutralization of special elements in SseStream._transform() when generating server-sent events output from user-influenced message.type or message.id fields. A remote attacker can supply crafted newline characters in these fields to inject arbitrary SSE events, spoof event types, and corrupt reconnection state.
Exploitation requires developer code that maps user-influenced data into the type or id fields of SSE messages.
Remediation
Install update from vendor's website.