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Crypted image or just a crypted password?

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H!

I generally use a pretty long password while making an image with Acronis True Image 2014 (since 2008). The encrypting algorithm is normally AES 128 or more.

Question is: Is just the password AES-protected or is the whole image I made?
If only the password is AES-protected, how easy is to access the data in the password protected image (reading raw data using Linux or else), i.e. in the case I lost the password? Is there a master password or can it be reset by Acronis?

Can someone help?

Greetz,
OT

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I don't know what is the implementation here, but I have to believe that the contents is actually encrypted using the AES algorithm using a key generated based on the password and maybe some additional information like a salt. Typically, the password is not stored in the archive, but a enhanced hash of the password is stored there. When an app tries to access the file, it has to ask for the password, recreate the hash, compare with the hash stored in the file, then recalculate the AES key and start decrypting the file.

If you lose the password, there is no way to unlock the file, aside from brute forcing it. It cannot be reset by Acronis, for local backups. I don't know about remote backups.

Brute forcing a password requires some software solution based on the structure of the target file, and then raw computing power. Some common hash algorithms used for passwords, like MD5 and SHA1 are optimized for speed. The key is to have a long password, since a 7-character password, mixed case, all symbols could be cracked under a handful of hours on a GPU, depending on the algorithm. I do not know which hashing algorithm is used in ATI, but the industry starts using slower algorithms.

Hi Pat!

Thanks for clearing this up.
Would be helpful to have something certain from the official site, if it really like you said: the whole file is encrypted and which algorithm is used.

We have archives stored with password (12 characters), that are shipped from one location to the central (low wire connection). If it get's lost on the way, it's bad, but we have to make sure, that others wit ATI can not open or access the data.

Greeting,
OT