The vulnerability arises because the extension permits a request-provided additionalFilters parameter to register a named siteHash filter before the system's own siteHash filter is applied. The query builder does not overwrite an already-registered named filter, enabling a visitor in a shared Solr core environment to read public documents from other TYPO3 sites. The same root cause affects the suggest top-results path when suggest functionality is enabled.

An attacker can read public documents belonging to other sites hosted on the same shared Solr core, potentially exposing data across site boundaries. This impacts data confidentiality but does not require privileges or user interaction. There are no known exploits in the wild at this time.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary workaround is indicated in the available data. Users should monitor TYPO3 vendor advisories for updates and consider restricting access to shared Solr cores or disabling suggest functionality until a fix is available.