CVE-2026-53519 Nezha Monitoring: Pre-auth path traversal via /dashboard.. prefix confusion leaks jwt_secret_key
Unauthenticated attackers can read sensitive configuration files, including JWT secrets, via path traversal in the dashboard handler.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-53519?
CVE-2026-53519 is a critical path traversal vulnerability in nezhahq nezha, published on 12 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-22
Which versions are affected by CVE-2026-53519?
3 open source packages ship an affected version, including github.com/nezhahq/nezha.
| Package | Affected | Fixed in |
|---|---|---|
github.com/nezhahq/nezha Go | All versions | None |
github.com/nezhahq/nezha Go | All versions | 2.0.13 |
github.com/nezhahq/nezha Go | All versions | 2.0.13 |
How do I fix CVE-2026-53519?
Upgrade github.com/nezhahq/nezha to 2.0.13 or later.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-53519 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-53519 exists.
Public exploit code: 1 Nuclei template and 2 proofs of concept on GitHub.
Sources
Also known as GHSA-5c25-7vpj-9mqh, GO-2026-5828.