---
cve: "CVE-2026-43921"
severity: "HIGH"
cvss: 8.9
epss: "27%"
vendor: "fossbilling"
kev: false
exploited: false
published: "2026-07-06 22:16:49"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-13T07:43:42+02:00"
---

# CVE-2026-43921

> 8.9 HIGH · 🧪 PoC

## Beschreibung

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.

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Hoch | good |
| UI Interaktion | Keine | bad |

## Patch verfügbar (OSV)

- 3bd35f5b2921d8a26a403142ae0408f95e6463cc (Commit)

## Referenzen

- <https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-v4j9-w6pj-38w5>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-43921) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_