CVE-2026-31889: Shopware vulnerable to a potential take over of app credentials

We identified and fixed a vulnerability in the Shopware app registration flow that could, under specific conditions, allow attackers to take over the communication channel between a shop and an app. By abusing app re‑registration, an attacker could redirect app traffic to an attacker‑controlled domain and potentially obtain API credentials intended for the legitimate shop. We have no evidence that this vulnerability has been exploited.