Boris Johnson’s phone number online for years

U.K. Prime Minister Boris Johnson’s personal mobile phone number has been available on the internet for years, after being included in a 2006 press release during his time on the opposition frontbench, British gossip newsletter Popbitch reported on Thursday.

London Playbook confirmed the press release was still online and the number was indeed the prime minister’s, though as of Friday morning it was unclear whether Johnson still used it. “This person’s phone is switched off. Please try later or send a text,” a female voice responded upon calling.

The news has national security implications, as it could expose the prime minister to threats such as SMS phishing. “This is extremely worrying with massive security implications,” said Labour MP Kevan Jones, a member of the intelligence and security committee and a former defense minister.  “It needs to be investigated as a matter of urgency … It leaves the prime minister very vulnerable.”

With a politician’s phone number, a malicious actor could send messages with links that would allow their mobile to be hacked, the former security official said, which could grant access to apps including emails. A hacker could also intercept messages or pose as the sender to contact others. It would also be easier to geolocate the phone.

But one former senior government security official said the revelations aren’t that serious, as hostile states like Russia and China are already likely to be able to gain access to high-profile politicians’ phone numbers in other ways, and people in government are told to treat their phones as if they were already compromised.

POLITICO also found at least three other Cabinet ministers’ personal mobile phone numbers online.

Downing Street declined to comment.

The problem is not uniquely British. European officials‘ phone numbers have recently circulated online as a result of a massive Facebook data leak, with European Justice Commissioner Didier Reynders, Luxembourg Prime Minister Xavier Bettel and multiple French ministers among those affected.

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