Microsoft ASP.NET Application Folder Information Disclosure Vulnerability



Date Discovered

July 11, 2006


ASP.NET is prone to an information-disclosure vulnerability. This issue is due to a failure in the applications to properly validate user-supplied input. An attacker can exploit this issue to retrieve potentially sensitive information. Information retrieved may aid in further attacks.

Technologies Affected

  • Microsoft .NET Framework 2.0


Block external access at the network boundary, unless external parties require service.
If possible, block access to the server at the network perimeter to allow only trusted hosts and networks to access the resources.

Deploy network intrusion detection systems to monitor network traffic for malicious activity.
NIDS may detect attacks against web applications. Monitor logs on a regular basis.

Run all software as a nonprivileged user with minimal access rights.
If possible, run the hosting webserver with the least privileges required while still maintaining functionality.

Evaluate read, write, and execute permissions on all newly installed software.
Removing the 'Read' permissions from all ASP.NET Application Folders will mitigate exposure to this issue.

The vendor has released an advisory to address this issue in supported versions of the affected software.



Urs Eichmann is credited with the discovery of this vulnerability.

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