A cross-site scripting (XSS) vulnerability in the Admin Control Panel of vBulletin 5.7.5 and 6.0.0 allows attackers to execute arbitrary web scripts or HTML via the /login.php?do=login url parameter.

vBulletin before 5.5.6pl1, 5.6.0 before 5.6.0pl1, and 5.6.1 before 5.6.1pl1 has incorrect access control.

vBulletin 5.5.4 allows SQL Injection via the ajax/api/hook/getHookList or ajax/api/widget/getWidgetList where parameter.

vBulletin through 5.5.4 mishandles custom avatars.

vBulletin before 5.5.4 allows clickjacking.

vBulletin through 5.5.4 mishandles external URLs within the /core/vb/vurl.php file and the /core/vb/vurl directories.

vBulletin 5.x through 5.5.4 allows remote command execution via the widgetConfig[code] parameter in an ajax/render/widget_php routestring request.

In vBulletin through 5.3.x, there is an unauthenticated deserialization vulnerability that leads to arbitrary file deletion and, under certain circumstances, code execution, because of unsafe usage of PHP's unserialize() in vB_Library_Template's cacheTemplates() function, which is a publicly exposed API. This is exploited with the templateidlist parameter to ajax/api/template/cacheTemplates.

vBulletin through 5.3.x on Windows allows remote PHP code execution because a require_once call is reachable with an unauthenticated request that can include directory traversal sequences to specify an arbitrary pathname, and because ../ traversal is blocked but ..\ traversal is not blocked. For example, an attacker can make an invalid HTTP request containing PHP code, and then make an index.php?routestring= request with enough instances of ".." to reach an Apache HTTP Server log file.

vBulletin 5.x through 5.1.6 allows remote authenticated users to bypass authorization checks and inject private messages into conversations via vectors related to an input validation failure.

In vBulletin before 5.3.0, remote attackers can bypass the CVE-2016-6483 patch and conduct SSRF attacks by leveraging the behavior of the PHP parse_url function, aka VBV-17037.

The vB_Api_Hook::decodeArguments method in vBulletin 5 Connect 5.1.2 through 5.1.9 allows remote attackers to conduct PHP object injection attacks and execute arbitrary PHP code via a crafted serialized object in the arguments parameter to ajax/api/hook/decodeArguments.

Cross-site scripting (XSS) vulnerability in admincp/apilog.php in vBulletin 4.2.2 and earlier, and 5.0.x through 5.0.5 allows remote authenticated users to inject arbitrary web script or HTML via a crafted XMLRPC API request, as demonstrated using the client name.

SQL injection vulnerability in vBulletin 5.0.4 through 5.1.3 Alpha 5 allows remote attackers to execute arbitrary SQL commands via the criteria[startswith] parameter to ajax/render/memberlist_items.