bluespice/wiki container: Insecure default configuration of service token authentication allows privilege escalation to sysop

Initialization of a Resource with an Insecure Default vulnerability in Hallo Welt! GmbH BlueSpice (container image bluespice/wiki) allows privilege escalation. The default value of $mwsgTokenAuthenticatorServiceCIDR in the container's LocalSettings.php was intended to restrict internal service authentication to the container network, but evaluated to an empty string when the environment variable WIKI_SERVICE_TOKEN_AUTH_ALLOWED was not set. An empty value disables the IP restriction in the token authenticator component (mwstake/mediawiki-component-token-authenticator). As a result, any user with read access to the wiki (anonymous users on publicly readable wikis) could obtain an application token from the REST API and use it to get a session with sysop privileges as the internal service user. This issue affects BlueSpice: from 5.2.3 before 5.2.7, and the 5.2.7 container images published before 2026-10-19 15:37 UTC.