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TI-2026-23321 Aliases CVE-2026-29204GHSA-5j8p-mmp9-6fj8

Authorization bypass in WebPros WHMCS

Priority MEDIUM 47CWE-639Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-639.

Summary

Insufficient ownership check in `clientarea.php` allows an authenticated client area user to submit requests using another user’s `addonId` without any ownership validation leading to unauthorized access to the victim's account.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00319 24th percentileScored 2026-11-07
Fix Fixed WHMCS (WebPros): 18.13.3, 9.0.4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

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

Affected products

VendorProductAffected versionsFixed inStatusSource
WebProsWHMCS7.4.0 – 18.12.2; 18.13.0 to before 18.13.3; 9.0.0 to before 9.0.418.13.3, 9.0.4Patch availableCNA
  • WHMCS VendorWebPros Affected 7.4.0 – 18.12.2; 18.13.0 to before 18.13.3; 9.0.0 to before 9.0.4 Fixed in 18.13.3, 9.0.4 Patch available CNA

Remediation

  • Fix · CNA WHMCS (WebPros) Fixed in 18.13.3, 9.0.4

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-29204
  2. 2026-10-03 Alias added: GHSA-5j8p-mmp9-6fj8

References

Other 1

  • TI-2026-30342 WebPros cPanel and WHM Authentication Bypass via Login Flow KEVCVSS 4.0CRITICAL 9.3
  • TI-2026-46792 Eval injection in cPanel 11.138.0.0 and earlier allows remote authenticated users to execute arbitrary code as root. CVSS 4.0HIGH 8.7
  • TI-2025-40383 Plesk Obsidian versions 8.0.1 through 18.0.73 are vulnerable to a Denial of Service (DoS)… CVSS 3.1HIGH 7.5
  • TI-2026-23322 Incorrect privileges management and insufficient path filtering allow to read arbitrary… CVSS 3.1HIGH 8.6
  • TI-2026-47685 Deserialization of untrusted data in WebPros WHMCS CVSS 4.0CRITICAL 9.3
  • TI-2026-23317 Authorization bypass in WebPros Comet Backup CVSS 4.0CRITICAL 9.9
See all 50 →

Sources

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