CVE-2026-33543

FOSSBilling is a free, open-source billing and client management system. Versions 0.7.2 and prior expose a guest API endpoint, /api/guest/staff/create, intended for initial administrator bootstrap. Due to a flawed admin-existence check, the endpoint remains usable after an administrator already exists. The flawed guard check uses is_countable() on a value that returns a Model_Admin object or null rather than a countable type, causing the expression to always evaluate as true and bypass the intended protection. As a result, an attacker can reach the unprotected endpoint to create a new administrator account and immediately authenticate, gaining a fully privileged admin session even when an admin already exists. This issue has been fixed in version 0.8.0.

CVSS

No CVSS.

References

Link	Resource
https://github.com/FOSSBilling/FOSSBilling/releases/tag/0.8.0
https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-28mh-j262-q49w

Configurations

No configuration.

History

24 Jun 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-24 21:16

Updated : 2026-06-25 19:58

NVD link : CVE-2026-33543

Mitre link : CVE-2026-33543

CVE.ORG link : CVE-2026-33543

JSON object : View

Products Affected

No product.

CWE

CWE-288

Authentication Bypass Using an Alternate Path or Channel

CWE-306

Missing Authentication for Critical Function

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