Open redirect vulnerability in exchweb/bin/redir.asp in Microsoft Outlook Web Access (OWA) for Exchange Server 2003 SP2 (aka build 6.5.7638) allows remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via a URL in the URL parameter.
URL Redirection to Untrusted Site The web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect.