CVE-2021-4391: 
WordPress vulnerability analysis and mitigation

The vulnerability CVE-2021-4391 affects the Ultimate Gift Cards for WooCommerce plugin versions 2.1.1 and below. This security issue was discovered by Jerome Bruandet from NinTechNet and was publicly disclosed on June 21, 2021. The vulnerability is related to a Cross-Site Request Forgery (CSRF) bypass due to missing or incorrect nonce validation in the mwbwgmsave_post() function (Wordfence Intel).

The vulnerability stems from improper nonce validation in the plugin's functionality. Specifically, the issue occurs due to missing or incorrect nonce validation on the mwbwgmsave_post() function, which could allow unauthorized actions to be performed. The vulnerability has been assigned a CVSS score of 4.3 (Medium severity) (NVD, Wordfence Intel).

The vulnerability could allow attackers to bypass CSRF protections, potentially enabling them to perform unauthorized actions in the context of authenticated users. This could lead to unauthorized modifications of gift card settings or other plugin functionalities (NinTechNet Blog).

Users are advised to update the Ultimate Gift Cards for WooCommerce plugin to version 2.1.2 or later, which contains the fix for this vulnerability. The update implements proper nonce validation to prevent CSRF attacks (Wordfence Intel).