# Casso – Tự động xác nhận thanh toán chuyển khoản ngân hàng <= 4.1.1 - Missing Authorization to Unauthenticated Casso Account Disconnection

- **ID:** WPSEC-2026-1247
- **Plugin:** Casso Flow – Tự động xác nhận thanh toán chuyển khoản ngân hàng (`casso-tu-dong-xac-nhan-thanh-toan-chuyen-khoan-ngan-hang`), https://wordpress.org/plugins/casso-tu-dong-xac-nhan-thanh-toan-chuyen-khoan-ngan-hang/
- **Affected versions:** all versions before 4.2.0
- **Fixed in:** 4.2.0 (Update to 4.2.0 or later.)
- **Severity:** Medium 6.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L)
- **Weakness:** CWE-862
- **Usage among sites WPSec scans:** plugin Low, affected versions Low (as of 2026-10-19)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/casso-tu-dong-xac-nhan-thanh-toan-chuyen-khoan-ngan-hang
- **Fix released:** 2026-10-18
- **Published:** 2026-10-19
- **URL:** https://wpsec.com/vuln/WPSEC-2026-1247/

## Description

The Casso Flow plugin for WordPress is vulnerable to unauthorized modification of data via the 'oauth2_status' parameter in all versions up to, and including, 4.1.1, due to a missing capability check in the Casso_Admin_Page constructor. The constructor runs disconnectOAuth2() on any request to an admin endpoint (including admin-ajax.php), with no capability check and no nonce. This makes it possible for unauthenticated attackers to disconnect a Casso integration linked through OAuth: they can delete its webhooks, wipe the stored bank accounts and reset the plugin's payment settings.

## References

- https://wpsec.com/vuln/WPSEC-2026-1247/
- https://plugins.svn.wordpress.org/casso-tu-dong-xac-nhan-thanh-toan-chuyen-khoan-ngan-hang/tags/4.2.0/
- https://wordpress.org/plugins/casso-tu-dong-xac-nhan-thanh-toan-chuyen-khoan-ngan-hang/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-1247/

License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Free to use, share and adapt, also commercially, if you credit WPSec and link to this advisory.