CVE-2026-53645: high-severity vulnerability in FOSSBilling
FOSSBilling's missing self-edit prevention in staff permission management allows persistent privilege escalation
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.5epss 0.4%
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.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:H/SI:H/SA:L
Affected products
FOSSBilling · FOSSBillingRelated CVEs — FOSSBilling
In the same product, most dangerous first.
CVE-2026-28496CRITICALFOSSBilling: Server-side template injection in Twig template rendering enables information disclosure and RCEEPSS 1.9%CVE-2026-27604CRITICALFOSSBilling: Improper API Role Validation (system) Enables Unauthenticated Access to Privileged Admin FunctionsEPSS 1.3%CVE-2026-43920MEDIUMFOSSBilling: Unauthenticated update patcher endpoint allows remote maintenance executionEPSS 0.9%CVE-2026-53647MEDIUMFOSSBilling vulnerable to unauthenticated API key configuration disclosure via guest Serviceapikey get_info endpointEPSS 0.5%CVE-2026-43925MEDIUMFOSSBilling: Mass assignment of group_id in guest client registration allows unauthorized promo code useEPSS 0.5%CVE-2026-33543CRITICALFOSSBilling: Authentication bypass allows unauthenticated administrator creationEPSS 0.4%