CVE-2026-42331

FOSSBilling is a free, open-source billing and client management system. Prior to version 0.8.0, the Guest API invoice/update endpoint is missing an authorization check present in other invoice-related endpoints, allowing an unauthenticated user with knowledge of an invoice hash to modify the payment gateway associated with an unpaid invoice. An attacker who obtains an invoice hash, which may leak through shared URLs, referrer headers, or email links, can change the `gateway_id` on an unpaid invoice to any payment gateway configured in the system. This does not allow redirecting payments to an arbitrary external endpoint, as the gateway must already be installed and configured by an administrator. The practical impact is further limited by the `invoice_accessible_from_hash` system setting. Version 0.8.0 contains a patch. No known workarounds are available.

CVSS

No CVSS.

References

Link	Resource
https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-8755-w77f-3g7j
https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-8755-w77f-3g7j

Configurations

No configuration.

History

07 Jul 2026, 15:16

Type	Values Removed	Values Added
References	~~() https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-8755-w77f-3g7j -~~	() https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-8755-w77f-3g7j -

06 Jul 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-06 21:16

Updated : 2026-07-07 15:16

NVD link : CVE-2026-42331

Mitre link : CVE-2026-42331

CVE.ORG link : CVE-2026-42331

JSON object : View

Products Affected

No product.

CWE

CWE-306

Missing Authentication for Critical Function

CWE-863

Incorrect Authorization

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