CVE-2009-0550: Microsoft Ie

High severity, CVSS 9.3. EPSS: 11.8% chance of exploitation in the next 30 days.

Windows HTTP Services (aka WinHTTP) in Microsoft Windows 2000 SP4, XP SP2 and SP3, Server 2003 SP1 and SP2, Vista Gold and SP1, and Server 2008; and WinINet in Microsoft Internet Explorer 5.01 SP4, 6 SP1, 6 and 7 on Windows XP SP2 and SP3, 6 and 7 on Windows Server 2003 SP1 and SP2, 7 on Windows Vista Gold and SP1, and 7 on Windows Server 2008; allows remote web servers to capture and replay NTLM credentials, and execute arbitrary code, via vectors related to absence of a "credential-reflection protections" opt-in step, aka "Windows HTTP Services Credential Reflection Vulnerability" and "WinINet Credential Reflection Vulnerability."

Affected products

• Microsoft Ie: version 6.0 only
• Microsoft Internet Explorer: version 5.01 only; version 6 only; version 7 only
• Microsoft Windows 2000: any version
• Microsoft Windows Server 2003: any version
• Microsoft Windows Server 2008: any version
• Microsoft Windows Vista: any version; version gold only
• Microsoft Windows XP: any version

Published 2009-04-15. Last modified 2026-06-16.