Monday, September 20, 2010

Securing accounts on the Web


Few days ago, my partner Steven got his Google account compromised for a short period of time:
  • Tweet #1 at 8:52 PM on Sept. 9: Just received 2 calls from friends wondering if I'm being held at a London hotel. FYI, I'm not.
  • Tweet #2 at 12:23 AM on Sept. 10: Re: Being held in London. My Google account password was changed by an IP address in Nigeria. I've got it back now but with no Contacts.
  • Tweet #3: at 3:04 PM on Sept. 10: Re Stuck in London: I thought I had everything under control last night but needed Google Security Breach help to fix.
The thieves used his account to send a scam to few of his friends asking for money because he was supposedly blocked in London without resources.

If Steven's password was not very strong, there's no chance it has been discovered after only few attempts. At no time, Google reported that attempts to log into his account were conducted from computers with IP addresses in Liberia! Steven saw the first warning only when he recovered the access!

Encountered risk

The goal of these thieves was limited to getting money as soon as possible. So they reached out few of Steven's contacts, ones he contacts only occasionally, and they asked for a money to be transferred by Western Union. As they kept the control of his account, they would have been able to get the transaction MTCN (money transfer control number) via his inbox. Western Union maintains a page listing the Common Scams.

Others could have decided to change his password, to just spy his incoming message stream (these ones enabled the POP3 and IMAP accesses), to ask for password reset when Steven is not online, and then to steal his identity in many online services.

Because Steven reacted promptly and because his contacts detected the scam, the thieves did not get any benefit from this operation. They are probably trying to get someone else now, maybe someone from his contact list.

How to reduce the exposure

The first protection consists in defining strong passwords. A lot of services offer information about how to produce strong passwords. I would recommend this Microsoft site Strong Passwords | Microsoft Security—I'm confident that they don't provide the online password checker to enhance a grey dictionary ;)

The second protection would be to use a unique and strong password per account. This is probably the most difficult part! I may use probably 20 to 30 online services, some I use regularly, others I use very rarely. There's no way I can remember so many strong passwords...

My solution: Keepass + DropBox
  • Keepass is an open source password manager. The tool has been ported on many platforms: Windows, Mac, Linux, iPhone, Android, etc.—Full list on the download page.
  • DropBox (link with my referral id ;) is an online file sharing system that, thanks to a program installed on each computer/mobile in your network, maintains in sync the corresponding set of files. DropBox is a nice companion to Keepass as it duplicates your password database transparently, reducing the risk to loose the passwords if the original computer is lost.

The combination of the password generator and Keepass secure edit controls makes the tool especially useful:
  • It's easy to generate a strong passwords (remember: 16 characters or plus ;)
  • You don't have to remember them as a simple Ctrl+C / Ctrl+V allows to copy securely them in your browser! (the computer clipboard is automatically flushed after few seconds.)
In final, I just have one very strong password (30+ characters) to remember and to change periodically.

Known limitations

Some sites ask users to give a secret answer for a series of predefined questions. If you look at the Apple page below, you'll see that some questions might weaken users more than offering a protection... These days, it's pretty simple to find the responses online!

List of predefined security questions on website

Many sites only accepts alphanumerical characters only or don't accept passwords over 20 characters. Oddly enough, most of the bank websites I use prevent too long and too complex passwords! I guess they have other tools to detect intrusions...

List of predefined security questions on website

Last minute update

Today, Google announced on its Online Security blog that they will offer a Two-Step Authentication mechanism to log into Google services. This One-Time Password authentication is simpler than distributing a one-time password generator, as Amazon does for example, while providing a still strong security enhancement.

I hope it helps.
A+, Dom

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