Cross-site scripting (XSS) vulnerability in PunBB 1.2.6 and earlier allows remote attackers to inject arbitrary web script or HTML via Javascript contained in nested, malformed BBcode url tags.
https://exchange.xforce.ibmcloud.com/vulnerabilities/22234
http://www.vupen.com/english/advisories/2005/1708
http://www.securityfocus.com/bid/14808
http://www.securityfocus.com/archive/1/422267/100/0/threaded
http://www.securityfocus.com/archive/1/422088/100/0/threaded
http://www.punbb.org/changelogs/1.2.6_to_1.2.7.txt