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TI-2026-22084 Aliases CVE-2026-27708

FOSSBilling: IDOR in Servicecustom Client API allows cross-client data access

Priority LOW 31CWE-284Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-284.

Summary

FOSSBilling is a free, open-source billing and client management system. In versions 0.7.2 and prior, the Servicecustom Client API's __call method accepts an order_id parameter and fetches the associated order without verifying the authenticated client owns it, potentially exposing cross-client data through IDOR. An authenticated client can access any other client's custom service by guessing sequential order IDs. This can lead to a confidentiality breach — attackers can read client PII (name, email, phone, address, company details, VAT number) and service configuration data belonging to other clients. This issue has been fixed in version 0.8.0.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00364 30th percentileScored 2026-11-07
Fix Fixed FOSSBilling (FOSSBilling): 0.8.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
FOSSBillingFOSSBillingbefore 0.8.00.8.0Patch availableCNA
  • FOSSBilling VendorFOSSBilling Affected before 0.8.0 Fixed in 0.8.0 Patch available CNA

Remediation

  • Fix · CNA FOSSBilling (FOSSBilling) Fixed in 0.8.0

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-27708

References

Other 2

  • TI-2023-03258 SQL Injection in fossbilling/fossbilling CVSS 3.1CRITICAL 9.8
  • TI-2023-03719 Insufficient Session Expiration in fossbilling/fossbilling CVSS 3.1CRITICAL 9.8
  • TI-2023-03259 Unrestricted Upload of File with Dangerous Type in fossbilling/fossbilling CVSS 3.1HIGH 8.8
  • TI-2023-03261 Improper Neutralization of Formula Elements in a CSV File in fossbilling/fossbilling CVSS 3.1HIGH 8.0
  • TI-2026-30636 FOSSBilling missing authorization in guest Invoice API endpoints CVSS 4.0HIGH 7.7
  • TI-2023-03173 Code Injection in fossbilling/fossbilling CVSS 3.1HIGH 7.2
See all 43 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences