Open Source Point of Sale is a web based point-of-sale application written in PHP using CodeIgniter framework. Prior to 3.4.3, a Stored Cross-Site Scripting (XSS) vulnerability exists in the Daily Sales management table. The customer_name column is configured with escape: false in the bootstrap-table column configuration, causing customer names to be rendered as raw HTML. An attacker with customer management permissions can inject arbitrary JavaScript into a customer's first_name or last_name field, which executes in the browser of any user viewing the Daily Sales page. This vulnerability is fixed in 3.4.3.