Twitter is growing at phenomenal speed -- but this week's breach by a French hacker who accessed the accounts of Britney Spears, Barack Obama, and others proves it's time for the service to show a more mature attitude to security.A hacker calling himself "Hacker Croll" breached Twitter security and gained access to a staff member's administrative account, opening up millions of innocent accounts for potential abuse.

Twitter is keen to stress that no serious damage was done in the attack -- but it would have been so easy for the passwords of the likes of Lily Allen, Ashton Kutcher, and others to have been reset, with hackers planting malicious links onto their popular Twitter streams.

With more than 1 million people following Kutcher on Twitter, for instance, the potential for harm was considerable. Imagine if a Twitter update had been posted claiming to come from Demi Moore's hubby, but that really took followers to a Web page containing a drive-by malicious download?

It appears that this latest Twitter security breach occurred because a staff member had his Yahoo account broken into, and login information about his Twitter administration account was stolen.

Well, there's an easy way for Twitter to protect against this.

You see, when I log into Sophos' servers when I'm on the road (I've been attending conferences in Boston, San Francisco, and London for the past three weeks), I don't just use a username and password to gain access.

No, like many companies, my employer demands an extra level of authentication in the form of a hardware keyfob that creates a random number every 30 seconds. That means that even if my username and password get compromised, hackers won't be able to access my account or my company's internal servers, unless they also have physical access to the authentication device in my pocket.

Websites like Twitter, which are storing the personal information of millions of Internet users, need to grow up about security and ensure their own staff can log on to critical administration systems only if they can authenticate their identities with more than just a username and password.

If it's good enough for real-life businesses, then it should be good enough for Web 2.0 businesses, too.

Graham Cluley is senior technology consultant at Sophos, and has been working in the computer security field since the early 1990s. When he's not updating his other blog on the Sophos Website, then you can find him on Twitter at @gcluley. Special to Dark Reading.