The Pimcore Admin Classic Bundle provides a Backend UI for Pimcore. Full Path Disclosure (FPD) vulnerabilities enable the attacker to see the path to the webroot/file. e.g.: /home/omg/htdocs/file/. Certain vulnerabilities, such as using the load_file() (within a SQL Injection) query to view the page source, require the attacker to have the full path to the file they wish to view. In the case of pimcore, the fopen() function here doesn't have an error handle when the file doesn't exist on the server so the server response raises the full path "fopen(/var/www/html/var/tmp/export-{ uniqe id}.csv)". This issue has been patched in commit `10d178ef771` which has been included in release version 1.2.1. Users are advised to upgrade. There are no known workarounds for this vulnerability.
https://huntr.com/bounties/4af4db18-9fd4-43e9-8bc6-c88aaf76839c/
https://github.com/pimcore/admin-ui-classic-bundle/security/advisories/GHSA-c8hj-w239-5gvf
https://github.com/pimcore/admin-ui-classic-bundle/commit/10d178ef771097604a256c1192b098af9ec57a87