CVE-2026-27604

FOSSBilling is a free, open-source billing and client management system. Starting in version 0.5.4 and prior to version 0.8.0, an authorization bypass in the API role handling allows unauthenticated access to privileged `/api/system/*` endpoints. Because `system` resolves to the cron admin identity, attackers can invoke admin API methods without valid credentials, session, or CSRF token. Version 0.8.0 patches the issue. Some workarounds are available. Block external access to `/api/system/*` at reverse proxy/WAF, restrict API access by trusted source IPs only (`api.allowed_ips`), rotate all admin/client API tokens immediately, invalidate active sessions and reset high-privilege credentials, and/or review API request logs for suspicious `/api/system/` access and treat as potential incident.

CVSS

No CVSS.

References

Link	Resource
https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-57mv-jm88-66jc
https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-78x5-c8gw-8279
https://www.vulncheck.com/blog/fossbilling-auth-bypass-ssti-rce

Configurations

No configuration.

History

23 Jun 2026, 15:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-23 15:16

Updated : 2026-06-23 16:16

NVD link : CVE-2026-27604

Mitre link : CVE-2026-27604

CVE.ORG link : CVE-2026-27604

JSON object : View

Products Affected

No product.

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

CWE-306

Missing Authentication for Critical Function

CWE-862

Missing Authorization

CWE-863

Incorrect Authorization

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