Microsoft XML Core Services (aka MSXML) 3.0 and 6.0 does not properly restrict the information transmitted by Internet Explorer during a download action, which allows remote attackers to discover (1) full pathnames on the client system and (2) local usernames embedded in these pathnames via a crafted web site, aka "MSXML Entity URI Vulnerability."
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2014/ms14-033
http://www.securityfocus.com/bid/67895