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Re: Backdoor not recognized by Kaspersky
From: KUIJPERS Jimmy <jimmy.kuijpers () swift com>
Date: Thu, 04 Mar 2004 14:29:46 +0100

Hehehe, encrypted is a big word. Especially for a zip file. The contents can most certainly be read. Also be email 
gateways and virusscanners. Passwords can be cracked. There are special tools that can extract the contact of a
password protected zip file without knowning the password. To cut is short, the information is "reshufled" or rather 
compressed but NOT encrypted at all!

I think eventrough e-mail is not intented as a file transfer utility. For the common people it is the only way they 
know how they can send some files to their friends and co-workers. So I do not think that we should block all
executables and compressed files by default.

Rather following the suggestion made to stop accepting mail from spoofed mail relays makes much more sense to me. If 
that solution is workable I think it could solve alot of problems related to spam.

my 2cts

"Aditya, ALD [Aditya Lalit Deshmukh]" wrote:

The zip's contents can
be seen without the password, just not unpacked...no cracking it required.

now winrar has a option to encrypt file names with a password, me thinks pkzip with the 64 bit compression also has 
that feature... how are we going to deal with this ? by stopping all the compressed mail at the email gateway ?

we do have one solutions: all the mail headers are spoofed so just stop accepting mail from spoofed host, this should 
solve your spam problem also

You should be blocking executables by policy anyway, yes?

that is always being done by the all the people in this day and age, only now we seem to forget to add the compressed 
file format that are encrypted so that their file contects cannot be seen ?


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