CVE-2026-40077: CWE-184: Incomplete List of Disallowed Inputs in henrygd beszel
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.
AI Analysis
Technical Summary
Beszel versions before 0.18.7 have an access control weakness (CWE-184) where some API endpoints accept user-supplied system IDs without proper authorization checks. System IDs are random 15-character alphanumeric strings, and container IDs are 12-digit hexadecimal strings. Although these IDs are not broadly exposed, authenticated users may enumerate them via the web API. This allows unauthorized read access to system data through these endpoints. The vulnerability was addressed and fixed in version 0.18.7.
Potential Impact
The vulnerability allows any authenticated user to access API routes for systems they do not have permission to access if they can enumerate valid system and container IDs. The impact is limited to unauthorized read access (confidentiality loss) without affecting integrity or availability. The CVSS vector indicates low impact with a score of 3.5, requiring high attack complexity and low privileges.
Mitigation Recommendations
Upgrade beszel to version 0.18.7 or later where this vulnerability is fixed. Since the vendor advisory confirms the issue is resolved in 0.18.7, applying this official fix fully mitigates the risk. No additional mitigation steps are indicated.
CVE-2026-40077: CWE-184: Incomplete List of Disallowed Inputs in henrygd beszel
Description
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Beszel versions before 0.18.7 have an access control weakness (CWE-184) where some API endpoints accept user-supplied system IDs without proper authorization checks. System IDs are random 15-character alphanumeric strings, and container IDs are 12-digit hexadecimal strings. Although these IDs are not broadly exposed, authenticated users may enumerate them via the web API. This allows unauthorized read access to system data through these endpoints. The vulnerability was addressed and fixed in version 0.18.7.
Potential Impact
The vulnerability allows any authenticated user to access API routes for systems they do not have permission to access if they can enumerate valid system and container IDs. The impact is limited to unauthorized read access (confidentiality loss) without affecting integrity or availability. The CVSS vector indicates low impact with a score of 3.5, requiring high attack complexity and low privileges.
Mitigation Recommendations
Upgrade beszel to version 0.18.7 or later where this vulnerability is fixed. Since the vendor advisory confirms the issue is resolved in 0.18.7, applying this official fix fully mitigates the risk. No additional mitigation steps are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-09T00:39:12.205Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69d7ff941cc7ad14da10e9de
Added to database: 4/9/2026, 7:35:48 PM
Last enriched: 4/17/2026, 11:53:25 AM
Last updated: 5/25/2026, 12:22:42 PM
Views: 91
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