CVE-2026-112374

FOSSBilling before 0.8.9 contains a Cross-Site Request Forgery vulnerability in the staff guest login endpoint (POST /api/guest/staff/login) that allows remote attackers to force authentication because checkGuestClientAuthentication() only allowlists client_login and client_create, leaving staff_login without CSRF or Origin validation. Attackers can host an auto-submitting HTML form with attacker-controlled credentials to silently log a victim's browser into the attacker's staff account.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/FOSSBilling/FOSSBilling/releases/tag/0.8.9
https://github.com/FOSSBilling/FOSSBilling/security/advisories/GHSA-h7w3-wp25-gf86
https://www.vulncheck.com/advisories/fossbilling-before-login-csrf-via-staff-guest-login-api

Configurations

No configuration.

History

30 Oct 2026, 13:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-30 13:18

Updated : 2026-10-30 13:18

NVD link : CVE-2026-112374

Mitre link : CVE-2026-112374

CVE.ORG link : CVE-2026-112374

JSON object : View

Products Affected

No product.

CWE

CWE-352

Cross-Site Request Forgery (CSRF)

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