CVE-2025-49592: n8n allows open redirects via the /signin endpoint

This is an Open Redirect (CWE-601) vulnerability in the login flow of n8n. Authenticated users can be redirected to untrusted, attacker-controlled domains after logging in, by crafting malicious URLs with a misleading redirect query parameter.

This may lead to:

• Phishing attacks by impersonating the n8n UI on lookalike domains (e.g., n8n.local.evil.com)
• Credential or 2FA theft if users are tricked into re-entering sensitive information
• Reputation risk due to the visual similarity between attacker-controlled domains and trusted ones

The vulnerability affects anyone hosting n8n and exposing the /signin endpoint to users.