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Dropbox Flaws | TechSNAP | 1

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Get the full details are two major issues with Dropbox, that are simply built into the core of the software/service.

Plus WordPress has undergone a multi-server hack, and Facebook gives away their plans for the ultimate data center!

iTunes & RSS Feeds:

Show Notes:

WordPress gets hacked:
Story 1
Story 2

-multiple servers got hacked
-facebook and twitter API keys exposed
-non-opensource code and partner code exposed
-they recommend if you use the same password elsewhere you should change it (does this mean they are not doing secure hashes?)

Facebook Topic:
Facebook gives away detailed schematics etc from it’s datacenters under an open license
-Custom power supply, only one voltage 10.5v
-harddrives (up to 6) powered by the motherboard, BIOS staggers drive start by 5 seconds each to deal with inrush current
-open cases, uses large scale air mover at the rack level instead of a large number of smaller fans per server
-power supplies have an AC feed, and a DC feed from UPS for backup (this is different from googles design, which placed a separate DC battery in each server, directly connected to the motherboard (circumventing the PSU). did this power the drives too? googles design is mostly secret)

Comodo Topic:

-SSL is the only thing standing between you and the eavesdroppers
-SSL makes sure you are talking to the real site
-if an SSL CA is compromised, someone could get a seemingly legitimate certificate for and setup a rouge wireless AP at your local starbucks, now he has not only your password, but all of your emails.
-once they have your email, they can reset your passwords for everything else

Comodo CA issues certs for major domains:,1

-EFF finds 37,000 SSL certificates issues for unqualified domain names

-EFF SSL Observatory

Comodo’s plans to solve the problem:

Microsoft patch to blacklist certs

More and more sites are offering SSL, or even doing SSL by default. This can be important if you are accessing things via wifi, especially if it is a public hotspot. This compromise means that it was possible for someone to have a valid certificate for skype and to sniff your credentials right out of the air.

Comodo SSL Article by Allan:

Dropbox security:
Dropbox insecure by design, if you upload one file w/ the app, hacker can access everything, even if you reformat

-problem with the authentication system
-uses only a host_id to authenticate devices. host_id is not related to a hardware hash, or your password.
-host_id is stored as plain text in a config.db SQLite db
-the same host_id can be used on multiple machines/devices
-so if someone copies your config.db, they can access you files without you knowing
-changing your password would not stop someone, as the host_id would still be valid
-because the host_id is not unique per device, you would not notice a new device
-once compromised, even if you reformat and change your passwords, the attacker could still access your files
-the only way to stop the attacker is to realize you have been compromised, and remove the effected device(s) via the dropbox control panel
-easy fix: include the password and some details (system name/type, hardware info) in the seed for the hash that is used as the host_id, automatically invalidate all host_ids when a password is changed.

Second Dropbox Flaw:

-Article mentions Tarsnap, written by Colin Percival, the FreeBSD Security officer. he wrote his own blog entry about a different backup company claiming to use the same encryption as banks and the military, see here:
-Files are encrypted once, using a key controlled by Dropbox. Dropbox policy allows them to decrypt and render your files to law enforcement. A real secure system would not allow Dropbox or law enforcement to access the files.
-AES is approved by the NSA to encrypt classified documents, such as ones classified Restricted, no-forn, confidential, secret, and top secret (top secret requires 256 bit keys, lower classifications only require 128 bit)
-There are US standards covering the use of encryption to protect CONFIDENTIAL, SECRET, and TOP SECRET information; but merely using 256-bit AES is nowhere near enough: The entire encryption system needs to be approved (including block cipher modes, key management, vulnerability to side channel attacks, et cetera), not merely the choice of block encryption algorithm.