CVE-2026-53645 — FOSSBilling's missing self-edit prevention in staff permission management allows persistent privilege escalation

Description (CNA)

FOSSBilling is a free, open-source billing and client management system. Versions prior to 0.8.0 allow a low-privileged staff account to grant arbitrary module permissions to itself through the admin API, resulting in persistent privilege escalation. A staff user that only has `staff.create_and_edit_staff` can call `/api/admin/staff/permissions_update` targeting their own account and write any permission structure, bypassing the intended role-based access control boundary. Version 0.8.0 patches the issue. Some workarounds are available. Restrict the `staff.create_and_edit_staff` permission to only highly trusted staff members and/or use a reverse proxy or WAF to restrict access to `/api/admin/staff/permissions_update` to specific trusted roles.

Affected (CNA)

Vendor / product	Versions
FOSSBilling / FOSSBilling	affected < 0.8.0

CWE

CWE-269

References

https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-4hf7-xxxw-64rm

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.