UK operators say voicemail weaknesses fixed

Operators are taking steps to reassure customers their voicemail systems are secure amid the phone hacking scandal

As the phone hacking saga continues to grip the U.K., mobile operators contend that spying on someone's voicemail messages wouldn't be possible today as several weaknesses in the systems have been eliminated.

Reporters and private investigators working for the News of the World tabloid, owned by Rupert Murdoch's News Corp., are accused of repeatedly illegally accessed the voicemail messages of more than 4,000 people -- from royal family members to an abducted and later murdered 13-year-old girl in 2002 -- for information for news stories.

The phone hacking scandal has rocked the U.K., with the arrest of a top adviser to Prime Minister David Cameron and two senior officials at Scotland Yard resigning so far. Murdoch, his son James, and Rebekah Brooks -- formerly chief executive of News International and editor of the now-shuttered News of the World tabloid -- were due to answer questions in Parliament on Tuesday.

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As the phone hacking saga continues to grip the U.K., mobile operators contend that spying on someone's voicemail messages wouldn't be possible today as several weaknesses in the systems have been eliminated.

Reporters and private investigators working for the News of the World tabloid, owned by Rupert Murdoch's News Corp., are accused of repeatedly illegally accessed the voicemail messages of more than 4,000 people -- from royal family members to an abducted and later murdered 13-year-old girl in 2002 -- for information for news stories.

The phone hacking scandal has rocked the U.K., with the arrest of a top adviser to Prime Minister David Cameron and two senior officials at Scotland Yard resigning so far. Murdoch, his son James, and Rebekah Brooks -- formerly chief executive of News International and editor of the now-shuttered News of the World tabloid -- were due to answer questions in Parliament on Tuesday.

The voicemail spying has been termed "phone hacking" but actually involved a series of nontechnical simple tricks crafted around the previously lax security controls for voicemail accounts.

In the U.K., private investigators and journalists allegedly gained access to voicemail accounts for famous people often by dialing an operator's dedicated voicemail line and then trying the default 4-digit Personal Identification Number (PIN) assigned to the account. That was highly successful since few of the victims changed the default PIN. And if they did change it, there was always the possibility of tricking -- or bribing -- a customer service representative at the operator into resetting the PIN to the default value.

Other ways accounts may have been accessed include successfully spoofing the victim's phone number. Many voicemail accounts are configured so that a PIN is not required if a person calls from their own telephone. Access could then be immediately gained if a number is successfully spoofed, although the practice is illegal in the U.K.

Compared to the early 2000s, operators have made it more difficult for the so-called hacking.

By default, at least four of the five major operators in the U.K. -- Three, T-Mobile, Vodafone and O2 -- block access to voicemail from anything other than the subscriber's own phone. To enable access from other devices, the subscriber must first set a PIN by dialing in from their own phone, closing off one of the major security errors that enabled mass hacking in the U.K.

Vodafone, Orange and T-Mobile also do not allow their subscribers to set lazy PINs, such as "1111" and "5678," again taking away more low-hanging fruit.

Vodafone will also lock out a person from their voicemail if the subscriber enters an incorrect code three times, preventing a "brute force" style of attack where PIN combinations are repeatedly tried. The subscriber then has to contact Vodafone's customer service representative, who will send out a new randomly generated four-digit PIN by SMS.

Customer service representatives at Three, Vodafone and O2 do not have access to voicemail PINs and can merely reset them. That prevents a spy from trying to bribe someone on the inside for the PIN.

The IDG News Service is a Network World affiliate.