[Full-disclosure] Decrypt info in referenced file @ web.config

[Richard Miles <richard.k.miles@xxxxxxxxxxxxxx>]

Hello

I'm doing a test and I obtained a copy of the web.config file, the
interesting is that there is a line like that "<add key="PasswordFile"
value="C:\Inetpub\site\Users.acl" />"  this called my attention to be
on the inetpub folder and I was able to download it.

It's with base64, when decoding it is messed up, so I believe it's encrypted.

I found something on the web.config that is related with encryption
and hashing, but I'm unsure if it's used to encrypt this file.

<machineKey validationKey="AutoGenerate" decryptionKey="AutoGenerate"
validation="SHA1" />
<add key="CryptoEngine" value="False" />
<add key="CryptoHashKey" value="SpartanLosHeros" />

SHA1 is a hash function, and based on the name of the file I believe
the contents contain usernames, so I don't believe they are using a
hash function.

The CryptoHashKey may be the key used to encrypt. But this
CryptoEngine configured to false sounds strange.

I find no reference to crypt algorithms on this file. Based on your
experience do you believe this CryptoHashKey is the key used to
encrypt this file? What algorithm? There is a default one used by
.NET?

I have no experience with .NET, someone with experience can point me
what it can be, or where discover the key and algorithm used?

Maybe a application that I enter the supposed key and the encrypted
data and it show me all the possibilities available with .NET?

Thank you

_______________________________________________
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/