The XmlImportExport plugin in MantisBT 1.2.17 and earlier allows remote attackers to execute arbitrary PHP code via a crafted (1) description field or (2) issuelink attribute in an XML file, which is not properly handled when executing the preg_replace function with the e modifier.
seclists.org/oss-sec/2014/q4/576
secunia.com/advisories/62101
www.debian.org/security/2015/dsa-3120
www.mantisbt.org/bugs/view.php?id=17725
www.securityfocus.com/bid/70993
exchange.xforce.ibmcloud.com/vulnerabilities/98572
github.com/mantisbt/mantisbt/commit/84017535
github.com/mantisbt/mantisbt/commit/bed19db9