While experts praise Twitter's decision to provide accountholders with two-factor authentication, they warn that additional security will still be needed to prevent the hijacking of high-profile accounts.
Twitter said on Wednesday that people who opted to take advantage of the service would be prompted to enter a six-digit code texted to their mobile phone each time they logged into the microblogging service. While such additional authentication is a bit more work, it increases the difficulty for hackers.
Twitter launched the service after a string of account hijackings. Since last month, a group calling itself the Syrian Electronic Army has taken credit for breaking into the accounts of the Associated Press, the Financial Times, National Public Radio and The Guardian. The group says it targets news media that are sympathetic to Syria's rebels.
The AP hack was particularly dramatic. The attackers posted false tweets saying there had been two explosions in the White House, and that President Barack Obama was injured. The bogus report to AP's 1.9 million followers caused the Dow Jones Industrial Average to drop more than 100 points before quickly recovering to erase the losses.
Twitter is not the first major Internet company to launch two-factor authentication. Google and Facebook also provide the service as an option.
While additional security is a positive, the new option will unlikely help news organizations, said Graham Cluley, senior technology consultant for the antvirus company Sophos. That's because such companies have many staff members around the world posting to the single Twitter account, which makes it impossible for them to use the same mobile phone.
"It's a complex problem to fix, and for that reason many media organizations may choose not to enable Twitter's additional security at this time," Cluley said on Sophos' blog on Thursday.
These organizations could use an intermediary service to act as proxy when posting to Twitter, Cluley said. But the companies would have to check that the service had proper security systems to keep out hackers.
For celebrities and the average Joe, having two-factor authentication turned on won't protect them against determined hackers who may resort to man-in-the-middle techniques to capture the six-digit passcode sent to a phone. Such techniques involve the hacker somehow sending a login page disguised as coming from Twitter to input the passcode. Once the hacker has the code, it can log into the account and lockout the legitimate user.
Also, personal computers infected with malware with remote access tools capable of stealing credentials would also bypass two-factor authentication, said Etay Maor, a fraud prevention solution manager at Trusteer.
Maor said Twitter should have required the additional authentication. "Security is important enough to be mandatory," Maor said.
In general, all best practices for account protection still apply for using Twitter. Companies should restrict access to the accounts and ensure that employees use strong passwords. In addition, employees should be trained to watch for malware-carrying email attachments sent through spear-phishing campaigns mean to steal credentials.
"This isn't about Twitter; it's about your own security and protecting your own company's brand and reputation," Nick Hayes, an analyst with Forrester Research, said in a blog post.