XSS in Langflow

CVE-2026-5026

The '/api/v1/files/images/{flow_id}/{file_name}' endpoint serves SVG files with the 'image/svg+xml' content type without sanitizing their content. Since SVG files can contain embedded JavaScript, an attacker can upload a malicious SVG that executes arbitrary JavaScript when viewed by other users, leading to stored cross-site scripting (XSS). This allows stealing authentication tokens stored in cookies, including JWT access and refresh tokens.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.002 (5.1th percentile) — read the EPSS interpretation.