Description
WordPress Plugin Flexible Checkout Fields for WooCommerce is prone to a security bypass vulnerability. Exploiting this issue may allow attackers to perform otherwise restricted actions and subsequently inject new fields and scripts into the WooCommerce checkout page. WordPress Plugin Flexible Checkout Fields for WooCommerce version 2.3.1 is vulnerable; prior versions may also be affected.
Remediation
Update to plugin version 2.3.4 or latest
References
https://wordpress.org/support/topic/malicious-access-plugin-woo-add-to-carts-by-linkflowusers/
https://plugins.svn.wordpress.org/flexible-checkout-fields/trunk/readme.txt
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