CVE-2026-43921
FOSSBilling is a free, open-source billing and client management system.
Overview
CVE-2026-43921 is a known-severity vulnerability. It was published on July 6, 2026.
Technical description
FOSSBilling is a free, open-source billing and client management system. Versions 0.6.10 through 0.7.2 have a PHP code injection vulnerability in FOSSBilling's `Config::prettyPrintArrayToPHP()` method. When configuration values are updated, string values are written into `config.php` without escaping single quotes. Because `config.php` is loaded via a bare `include` on every HTTP request, an attacker with admin privileges can inject arbitrary PHP code that executes on every subsequent request. Version 0.8.0 contains a patch. Some workarounds are available. Restrict admin access to trusted personnel only; audit `config.php` for unexpected PHP code; and/ or at the reverse proxy/WAF level, restrict access to admin API endpoints that modify configuration.
Remediation
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
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Frequently asked questions
What is CVE-2026-43921?
CVE-2026-43921 is a known-severity vulnerability. It was published on July 6, 2026.
How severe is CVE-2026-43921?
CVSS score information is not yet available for this vulnerability. Check back as the CVE record is updated by NVD analysts.
How do I fix or remediate CVE-2026-43921?
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-43921?
CyberStrike is an open-source, AI-augmented pentesting engine. Rather than flag a version number, it tests whether an issue like CVE-2026-43921 is actually reachable in your own applications and APIs, then verifies each finding before reporting it. That tells you if the weakness is a real, exploitable risk in your environment or a false positive you can safely deprioritize.