A cyberattack on Parliament has compromised dozens of email accounts belonging to parliamentarians, according to Sky sources.

On Saturday hackers attacked the email server for Parliament. This prompted the digital security team to shut down external access to MPs and peers' email accounts, which are still unavailable.

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.

Parliament's digital security team is continuing to investigate the attack.

But a statement from a parliamentary spokesperson confirmed claims by Sky sources and stated that "significantly fewer than 1% of the 9,000 accounts on the parliamentary network" have been compromised.


Those 9,000 accounts belong not only to senior ministers and other MPs and peers, but also to their staffers and to many civil servants. Sky sources have suggested that dozens of accounts have been identified as compromised at the moment.

It is not yet known whose accounts may have been compromised, how much information may have been stolen from them, or who was behind the attack.

Sensitive details in government ministers' emails should not have been compromised, Sky has been told, as ministers are expected to carry out confidential work from their departmental email accounts.

These are hosted on the gov.uk domain, rather than the potentially affected parliamentary accounts which are hosted on the parliament.uk domain.

The parliamentary spokesperson said the accounts which have been compromised "did not conform to guidance issued by the Parliamentary Digital Service" regarding password strength.

They added that as the affected accounts are identified, the individuals who operate them are being contacted and additional investigations will be conducted to identify whether any data has been stolen.

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".

Sky sources have confirmed that the attack was not targeted against particular accounts, but rather attempted to probe the email server used by Parliament.

"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," added the parliamentary spokesperson.

"This has been achieved and both Houses will meet as planned tomorrow."