CVE-2026-103905 [HIGH] – The authentication middleware of the JTL-Shop administration backend processes the plugin

The authentication middleware of the JTL-Shop
administration backend processes the plugin safe mode toggle on the admin
logout route before checking whether the requesting user is
authenticated. An unauthenticated remote attacker can therefore switch the shop’s
plugin safe mode on and off, which deactivates all installed plugins and their
functionality, such as payment and shipping integrations, resulting in a shop-wide
denial of service. The attack requires a single request and can be
automated against many installations.