Executive brief
Nezha Monitoring is a tool used by administrators to track the health and performance of servers and websites. A security flaw allows unauthorized users to discover "private" services that were intended to be hidden from the public dashboard. By accessing specific web addresses, an attacker can see the names and performance data of these internal services, potentially revealing sensitive information about a company's internal infrastructure.
Technical details
An information disclosure vulnerability exists in Nezha Monitoring due to inconsistent authorization checks across API endpoints. While the main service-listing endpoint correctly filters services marked with 'EnableShowInService: false', the 'listServerServices' and 'getServiceHistory' endpoints utilize raw data accessors that bypass this visibility flag. An unauthenticated attacker can perform a linear scan of server or service IDs to retrieve the names and performance metrics of private services. This occurs because the 'optionalAuth' group allows guest access, and the backend fails to re-verify the visibility status before emitting service identity data. The issue is addressed in version 2.0.14.
Affected products
- nezhahq Nezha Monitoring >= 2.0.0, < 2.0.14
Timeline
- 2026-05-26: advisory: GitHub Security Advisory published
- 2026-06-12: disclosed: CVE published to NVD
- 2026-06-12: patched: Fix released in version 2.0.14