The BlackBerry Attachment Service in Research in Motion (RIM) BlackBerry Enterprise Server (BES) 4.0 to version 4.0 Service Pack 2 allows attackers to cause a denial of service via a malformed Portable Network Graphics (PNG) file that triggers a heap-based buffer overflow.
https://exchange.xforce.ibmcloud.com/vulnerabilities/24063
http://www.vupen.com/english/advisories/2006/0127
http://www.securityfocus.com/bid/16204