XSS in Langgenius Dify

CVE-2026-21866

Dify is an open-source LLM app development platform. Prior to 1.11.2, Dify is vulnerable to a stored XSS issue when rendering Mermaid diagrams within chats. This occurs because Dify’s default Mermaid configuration uses securityLevel: loose…

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.000 (2.0th percentile) — read the EPSS interpretation.

Affected products

Weakness classification (CWE)

References