How secure is AES-256, but with an effective key length of 56-bits? I need to encrypt a few drives using Kaspersky Total Security.  I however noted something peculiar, Kaspersky's description of their cipher is: 


  Data will be protected using AES-256 encryption with a 56-bit effective key length?


Does this mean that they are using the same key generator that AES-256 uses but their key in reality isn't 256-bits long, instead 56-bits?
It would appear that this is as a consequence of the Wassenaar Arrangement (more detailed explanation). Basically, because cryptography falls under certain laws regarding munitions and arms trafficking there are restrictions on the strength of the cryptography you are allowed to sell (if the product is not a mass market product). It would appear that the limit on key size for symmetric algorithms is 56 bits. The exact verbage on the restriction is is:


  A "symmetric algorithm" employing a key length in excess of 56 bit


Source: Section 5. A. 2. a. 1. a (Page 87) of this document.

What I assume they do is something similar to zero pad a 56 bit key of random bits to a length of 256 bits so that the key is the correct size but the export restrictions are still met.

Edit: As otus points out, I neglected to mention that 56 bits is not a whole lot in regard to security. It's so small that EFF cracked a 56 bit DES key via brute force in 1998 with roughly $250,000 of custom hardware.