CVE-2026-40077
LowCVSS 3.5Exploitation Probability (EPSS)
Low risk12th percentile - higher than 12% of all known CVEs
Summary
Beszel is a server monitoring platform. Prior to 0.18.7, some API endpoints in the Beszel hub accept a user-supplied system ID and proceed without further checks that the user should have access to that system. As a result, any authenticated user can access these routes for any system if they know the system's ID. System IDs are random 15 character alphanumeric strings, and are not exposed to all users. However, it is theoretically possible for an authenticated user to enumerate a valid system ID via web API. To use the containers endpoints, the user would also need to enumerate a container ID, which is 12 digit hexadecimal string.
Risk Assessment
An authenticated user could access monitoring data for systems they are not authorized to view, potentially breaching confidentiality.
Recommendation
Update Beszel to version 0.18.7 or later.
Other vulnerabilities in Beszel
Original NVD description (English source)
Beszel is a server monitoring platform. Prior to 0.18.7, some API endpoints in the Beszel hub accept a user-supplied system ID and proceed without further checks that the user should have access to that system. As a result, any authenticated user can access these routes for any system if they know the system's ID. System IDs are random 15 character alphanumeric strings, and are not exposed to all users. However, it is theoretically possible for an authenticated user to enumerate a valid system ID via web API. To use the containers endpoints, the user would also need to enumerate a container ID, which is 12 digit hexadecimal string. This vulnerability is fixed in 0.18.7.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS