Session Management Flaw in FOSSBilling Affects User Authentication
CVE-2026-43918

8.7HIGH

Key Information:

Vendor

Fossbilling

Status
Fossbilling
Vendor
CVE Published:
6 July 2026

What is CVE-2026-43918?

FOSSBilling, a free and open-source billing and client management system, contains a vulnerability that fails to invalidate existing authenticated sessions when a client or staff/admin account is suspended or marked as inactive. Prior to version 0.8.0, the session identity loaders did not check the status of the account beyond its existence in the database. This oversight allows users with suspended or inactive accounts to maintain access until their session expires naturally, posing significant security risks. The issue has been addressed in the latest release, 0.8.0, which rectifies this flaw and enhances overall session management.

Affected Version(s)

FOSSBilling < 0.8.0

References

https://github.com/FOSSBilling/FOSSBilling/security/advis...
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https://github.com/FOSSBilling/FOSSBilling/releases/tag/0...
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CVSS V4

Score:
8.7
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.