CVE-2007-4040: Microsoft Outlook

High severity, CVSS 8.8. EPSS: 13.5% chance of exploitation in the next 30 days.

Argument injection vulnerability involving Microsoft Outlook and Outlook Express, when certain URIs are registered, allows remote attackers to conduct cross-browser scripting attacks and execute arbitrary commands via shell metacharacters in an unspecified URI, which are inserted into the command line when invoking the handling process, a similar issue to CVE-2007-3670.

Affected products

• Microsoft Outlook: any version
• Microsoft Outlook Express: any version

Published 2007-07-27. Last modified 2026-06-16.