Discuz! DiscuzX X3.4 allows remote attackers to bypass intended access restrictions via the archiver\index.php action parameter.

Discuz! DiscuzX X3.4 has XSS via the include\spacecp\spacecpspace.php appid parameter in a delete action.

Discuz! DiscuzX X3.4 has XSS via the include\spacecp\spacecpupload.php op parameter.

Discuz! DiscuzX through X3.4 has reflected XSS via forum.php?mod=post&action=newthread because data/template/1diyportalview.tpl.php does not restrict the content.

Discuz! DiscuzX X3.4 has XSS via the view parameter to include/space/spacepoll.php, as demonstrated by a mod=space do=poll request to home.php.

A vulnerability was found in DiscuzX up to 3.4-20200818. It has been classified as problematic. Affected is the function shownextstep of the file upload/install/include/installfunction.php. The manipulation of the argument uchidden leads to cross site scripting. It is possible to launch the attack remotely. Upgrading to version 3.4-20210119 is able to address this issue. The name of the patch is 4a9673624f46f7609486778ded9653733020c567. It is recommended to upgrade the affected component. The identifier of this vulnerability is VDB-258612.