CVE-2026-71531: High severity vulnerability

PrestaShop before 8.2.9 and 9.2.1 contains an authorization flaw in the Webservice API that allows an attacker holding a key restricted to one shop to act on data of every shop by submitting requests with idshop=all or idshopgroup=N, which expand the shop context without validating the key's actual shop associations and cause shopHasRight() to evaluate the expanded set as a disjunction. Attackers can exploit this flaw via classes/webservice/WebserviceRequest.php to read, modify, or delete data belonging to shops they are not authorized for, including full customer records such as email addresses, securekey, and password hashes across the installation.