summary_graph_functions.php in Mantis 0.17.3 and earlier allows remote attackers to execute arbitrary PHP code by modifying the g_jpgraph_path parameter to reference the location of the PHP code.
https://exchange.xforce.ibmcloud.com/vulnerabilities/9829
https://euvd.enisa.europa.eu/vulnerability/EUVD-2002-1101
http://www.securityfocus.com/bid/5504
http://www.debian.org/security/2002/dsa-153