Yellow alert over severe server peril
The vulnerability, which has been under active attack for several weeks, creates a mechanism for attackers to read any file on a web application server. Microsoft rates the flaw as only “important”, while independent security watchers such the the SANS Institute‘s Internet Storm Centre say that rating underestimates the risk posed by the flaw to online shops built using Microsoft’s developer tools. The ISC has raised the InfoCon status of the flaw from green to yellow.
Microsoft’s advisory provides more detail on the “information disclosure” flaw. It explains that “in Microsoft .NET Framework 3.5 Service Pack 1 and above, this vulnerability can be used by an attacker to retrieve the contents of any file within the ASP.NET application, including web.config” and that “this vulnerability can also be used for data tampering, which, if successfully exploited, could be used to decrypt and tamper with the data encrypted by the server”. Leer más “MS emergency fix plugs ASP.Net web development hole”