The investigation by Parliament’s digital security team is ongoing, but it now speculates that up to 90 accounts – or less than 1% of the network’s 9,000 users – may have been compromised in the attack.
The Houses of Parliament were targeted by hackers on Friday in an attack that sought to gain access to accounts protected by weak passwords.
“Investigations are ongoing, but it has become clear that significantly fewer than one percent of the 9,000 accounts on the parliamentary network have been compromised”, the parliamentary spokesman told the Press Association.
“As they are identified, individuals whose accounts have been compromised have been contacted and investigations to determine whether any data has been lost are under way”.
Russian Federation is suspected of being behind an unprecedented cyber attack on Westminster that targeted MPs, according to reports.
While the attack has now been contained, preliminary investigations suggest that there may have been a compromise of a large number of communications, potentially including those between constituents and their elected officials.
He wrote: ‘There’s something wrong with Parliamentary emails so if you did email me, can you send to email@example.com instead please?’
A parliamentary spokesman said: “Parliament’s first priority has been to protect the parliamentary network and systems from the sustained and determined cyber attack to ensure that the business of the Houses can continue”.
It comes just over a month after 48 of England’s NHS trusts were hit by a cyber-attack.
But Tory MP Andrew Bridgen said the attack could affect public confidence in parliamentary procedures.
Lib Dem peer Baron Rennard tweeted: ‘Cyber security attack on Westminster Parliamentary e-mails may not work remotely text urgent messages’.
An earlier statement described the attack involving hackers “carrying out a sustained and determined attack on all parliamentary user accounts in an attempt to identify weak passwords”.
“We have systems in place to protect member and staff accounts and are taking the necessary steps to protect our systems”.
International Trade Minister Liam Fox told ITV News said it was a “warning to everyone we need more security and better passwords”.
Dr Fox added: “We know that there are regular attacks by hackers attempting to get passwords”.
While the USA still tries to sort out how Russian cyberattacks played an influence on the recent presidential election, the British Parliament is now experiencing its own attack from hackers this weekend.
The National Crime Agency said it was working with the NCSC but the centre was “leading the operational response”.
“As a precaution we have temporarily restricted remote access to the network”.