CVE-2026-53519

Description

Nezha Monitoring is a self-hostable, lightweight, servers and websites monitoring and O&M tool. Prior to version 2.0.13, fallbackToFrontend in the dashboard-s NoRoute handler treats any URL whose raw string starts with /dashboard as an admin-frontend asset request. The check uses strings.HasPrefix, not a path-segment match, so the input /dashboard../data/config.yaml is accepted; strings.TrimPrefix leaves ../data/config.yaml; and path.Join(-admin-dist-, -../data/config.yaml-) normalizes to data/config.yaml — which os.Stat finds and http.ServeFile returns. No authentication required. This issue has been patched in version 2.0.13.