CVE-2026-53519: Nezha Monitoring path traversal in dashboard NoRoute handler

Executive brief

Nezha Monitoring is a dashboard used for server and service monitoring. A security flaw allows unauthenticated attackers to access sensitive configuration files and the system database by sending a specially crafted web request. This can lead to the theft of secret keys and administrative credentials, allowing an attacker to take full control of the monitoring dashboard and its managed data.

Technical details

A path traversal vulnerability exists in the 'fallbackToFrontend' handler of Nezha Monitoring due to improper URL prefix validation. The application uses 'strings.HasPrefix' to check for '/dashboard' without ensuring a proper path segment match, allowing requests like '/dashboard../' to bypass standard Go 'http.ServeFile' security guards. When processed, 'path.Join' normalizes the traversal, allowing an unauthenticated attacker to read files outside the intended directory. This primitive can be used to exfiltrate 'data/config.yaml' (containing the HS256 'jwt_secret_key') and 'data/sqlite.db', enabling the attacker to forge administrative JWTs and achieve full system compromise. The issue is fixed in version 2.0.13.

Affected products

• nezhahq Nezha Monitoring < 2.0.13

Timeline

• 2026-05-31: disclosed
• 2026-06-26: advisory: Updated advisory published

References

• https://api.github.com/users/riodrwn
• https://github.com/riodrwn
• https://api.github.com/users/riodrwn/gists%7B/gist_id%7D
• https://api.github.com/users/riodrwn/repos
• https://avatars.githubusercontent.com/u/42384611?v=4
• https://api.github.com/users/riodrwn/events%7B/privacy%7D