The PayPal app before 3.0.1 for iOS does not verify that the server hostname matches the domain name of the subject of an X.509 certificate, which allows man-in-the-middle attackers to spoof a PayPal web server via an arbitrary certificate.
itunes.apple.com/us/app/paypal/id283646709
news.cnet.com/8301-27080_3-20021730-245.html
online.wsj.com/article/SB10001424052748703506904575592782874885808.html
viaforensics.com/press-releases/viaforensics-uncovers-paypal-application-vulnerability.html
viaforensics.com/security/viaforensics-uncovers-significant-vulnerability-paypal-iphone.html
www.securityfocus.com/bid/44657
www.vupen.com/english/advisories/2010/2887
exchange.xforce.ibmcloud.com/vulnerabilities/63002