What are the security implications of Digital Lifeboat (or other p2p storage solutions)

Question

From Digital Lifeboat's about us section

Our solution is a distributed storage cloud service. Digital Lifeboat will compress and encrypt each file selected for backup. We then process your encrypted file with an Erasure Coding algorithm that creates many fragments of your file. Once these fragments are prepared for transfer into the Digital Lifeboat Cloud, we then securely send and store each of them outside of your home on different computers. These encrypted, erasure coded, fragments are invisible on their storage hosts.

Using advanced steganographic techniques we safely store encrypted, erasure coded, fragments on your PC from other members of the Digital Lifeboat cloud. These fragments are invisible to your computer and it operates as if they are not there. When you add more data to your hard drive, they will automatically be erased if they are in the way.

What are the security implications of this setup? My dad is looking into it (and when compared with the cost of Carbonite, et al it looks pretty attractive) as a personal storage solution.

What risks could this setup have?

Answer 1

Their model itself seems to be secure enough. Files are encrypted (with AES-256) and segmented on your computer before being sent to other people, the only way † to assemble your files and decrypt them is using information related to your account:

1. an index that contains the locations of segments and their order to assemble your file.
2. The decryption key.

If the service provider (Digital Lifeboat) keep their client application and their servers secure enough to prevent others from getting the above mentioned two pieces of information, then theoretically your files are secure. Also they claim to be reviewed by a security firm called Security Innovation

Not that the above is a very technical answer, but in case you're looking for a non-tech and quick answer:

My personal verdict that they seem to be secure enough as there doesn't seem to be any previous incident and their disclosed model appears to make sense.

Note: Make sure you follow common security standards. Different username/password from other accounts, strong password, secure password for the email account associated with your Digital Lifeboat account..

---

† Apart from specific vulnerabilities that the application or the service itself might have.

Answer 2

I remember someone being left with a bad impression about Digital Lifeboat in November 2012. His comment below was featured in the Security Now podcast.

I recently started getting unsolicited and unexpected email from Digital Lifeboat, an online PC backup service. It appears that somebody set up an account using my email address by mistake, so Digital Lifeboat have been sending me updates about the PC being backed up on the account, with links to their website. If I wanted to access this person's account, with all of their personal information and all of the data in their backup files, I simply have to go to the Digital Lifeboat website and request a password reset using my email address. It is just the customer's dumb luck that I am too scrupulous to do so. Even if I don't do anything, though, they are still not getting any notification emails - I am - and they will never be able to reset their own password because everything goes to my email address.

I tried unsuccessfully to contact Digital Lifeboat by email and their webpage so I could warn them about the risks they are taking by not verifying customers' email addresses during account creation, and possibly to find a way to contact the customer without invading their privacy. But none of that worked. So today I finally posted on their Facebook page and did receive a response from a man who initially did not understand the issue and then proceeded to tell me about an even bigger problem.

He wrote, quote, "I forgot that our two-factor cell phone authentication is currently disabled. When we disabled it, we left this gaping hole in our security. Wow, that's our screw-up. Thanks for bringing it to our attention. I'd like to delete this thread so as not to advertise this issue, and we'll address it internally." That thread was deleted, but not before I took a screenshot of it.

It worries me to think of all the people trusting this company with their personal information and backup data because they're not being told the truth. Digital Lifeboat touts "256-bit AES encryption to insure complete privacy and security of your data," but what good is that encryption when they don't bother to protect the customer's account? It's the same thing we were talking about earlier. They clearly have awful security practices, and I'm still not sure they even understand the initial problem I brought to their attention.

Answer 3

The main risks I can think of is actually the legal side of things. I am not a lawyer, but my understanding of this scheme is that they are putting other people's files on your computer. That makes you the server. If client 123 does a bad thing and stores a file and a segment of it gets stored on your computer, that could become evidence and end up with a man at your door with a badge wanting to take your hard drive in as evidence.

Additionally, it seems like it would be a rather wasteful system and potentially insecure since it is depending on other clients to store the information and based on how they describe it, it sounds like they are probably using direct I/O to write something outside the file tables on the hard drives (the part about it being invisible and automatically overwriting). If this is correct, then anything like a defrag would destroy all the data on a machine. The only way to try and overcome this is to MASSIVELY duplicate the file, but that means for every megabyte you put in, they'd need to do something like 10mb of storage on your machine for the system to have a chance of working reliably.

I certainly would not trust my data to it because I'd be worried about the chance of losing the data (which is still technically insecure since part of security in the broad sense is storing the data safely).

As far as unauthorized parties getting your data, ultimately, their internal practices may have a lot to do about that, but if they are secure, the scheme sounds fine. It would be difficult if not impossible for someone to get the pieces without your account and even then, the files would be encrypted. If you are the only one with the encryption key, it is secure even if they fail at concealing the index to the pieces or protecting your account, but I don't know how they do it exactly.