Cross-site scripting (XSS) vulnerability in phpBB 2.0.6d and earlier allows remote attackers to inject arbitrary web script or HTML via the (1) postdays parameter to viewtopic.php or (2) topicdays parameter to viewforum.php.
https://exchange.xforce.ibmcloud.com/vulnerabilities/15464
https://euvd.enisa.europa.eu/vulnerability/EUVD-2004-1802
http://www.securityfocus.com/bid/9866
http://www.securityfocus.com/bid/9865
http://www.phpbb.com/support/documents.php?mode=changelog#206