PrestaShop/paypal is an open source module for the PrestaShop web commerce ecosystem which provides paypal payment support. A SQL injection vulnerability found in the PrestaShop paypal module from release from 3.12.0 to and including 3.16.3 allow a remote attacker to gain privileges, modify data, and potentially affect system availability. The cause of this issue is that SQL queries were being constructed with user input which had not been properly filtered. Only deployments on PrestaShop 1.6 are affected. Users are advised to upgrade to module version 3.16.4. There are no known workarounds for this vulnerability.