CVE-2026-29204
Critical
Description
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.
SeverityCritical
CVSS9.1
Exploit probability—
Product
WHMCS
PublishedMay 12, 2026
First seenMay 12, 2026
How to fix
Update
- WebPros WHMCS18.13.3, 9.0.4 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| WebPros WHMCS | 7.4.0 ≤ v ≤ 18.12.2, 18.13.0 ≤ v < 18.13.3, 9.0.0 ≤ v < 9.0.4 | 18.13.3, 9.0.4 |
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