CVE-2026-27708: FOSSBilling: IDOR in Servicecustom Client API allows cross-client data access
FOSSBilling is a free, open-source billing and client management system. In versions 0.7.2 and prior, the Servicecustom Client API's call method accepts an orderid parameter and fetches the associated order without verifying the authenticated client owns it, potentially exposing cross-client data through IDOR. An authenticated client can access any other client's custom service by guessing sequential order IDs. This can lead to a confidentiality breach — attackers can read client PII (name, email, phone, address, company details, VAT number) and service configuration data belonging to other clients. This issue has been fixed in version 0.8.0.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
FOSSBilling (Servicecustom Client API)to a version that resolves this vulnerability.Fixed in 0.8.0
Event History
Frequently Asked Questions
What is the severity of CVE-2026-27708?
CVE-2026-27708 has a high severity rating of 7.1.
How does CVE-2026-27708 affect FOSSBilling?
CVE-2026-27708 allows unauthorized cross-client data access due to insufficient verification of the client owning the order_id.
What versions of FOSSBilling are affected by CVE-2026-27708?
Versions of FOSSBilling prior to 0.8.0 are affected by CVE-2026-27708.
How do I fix CVE-2026-27708?
To fix CVE-2026-27708, upgrade FOSSBilling to version 0.8.0 or later.
What type of vulnerability is CVE-2026-27708?
CVE-2026-27708 is classified as an Insecure Direct Object Reference (IDOR) vulnerability.