Tikiwiki is a web-based groupware and content management system, developed with PHP, ADOdb and Smarty.
A vulnerability in jhot.php allows for an unrestricted file upload to the img/wiki/ directory. Additionally, an XSS exists in the highlight parameter of tiki-searchindex.php.
An attacker could execute arbitrary code with the rights of the user running the web server by uploading a file and executing it via a filepath parameter. The XSS could be exploited to inject and execute malicious script code or to steal cookie-based authentication credentials, potentially compromising the victim's browser.
There is no known workaround at this time.
All Tikiwiki users should upgrade to the latest version:
# emerge --sync
# emerge --oneshot --verbose --ask ">=www-apps/tikiwiki-1.9.5"