Answer Checking Restored (Fri, 27 Jun 2014)

We are pleased to let you know that answer checking has now been restored to the website.

(Friday 27 June 2014: Answer Checking Restored)

Security Breach Update (Sun, 22 Jun 2014)

As many of you will be aware it was discovered on Sunday 15 June 2014 that Project Euler had been hacked. An immediate decision was made by the team to take the website offline and to make everyone aware, through the temporary front page, that we had reason to believe that the database had been compromised.

We would like to reinforce the recommendation we made when the breach was first discovered. If you use the same password on other websites and you have not changed them already then please do so as a matter of urgency.

In an attempt to remain as open as possible and to keep everyone informed we would like to provide a short update.

The hacker had managed to upload a file to the server which allowed them full access to the website, its structure, and the option to freely perform queries to the DB.

Due to this level of access it is highly likely that the hacker will have been able to obtain user information from the DB which includes email addresses and hashed passwords. Combined with access to the salting mechanism the integrity of weak passwords cannot be guaranteed.

Because we are still unclear how this breach occurred the full functionality of the website cannot be restored. However, the problem set remains accessible at the normal web address.

Please be assured that we continue to do what we can to fix it.

(Sunday 22 June 2014: Security Breach Update)

Security Breach (Fri, 20 Jun 2014)

On Sunday 15 June 2014 it was discovered that Project Euler had been hacked and a decision was made to take the website offline. Project Euler has existed since 2001 and after thirteen years of it being carefully nurtured to become what it has become today we hope you understand that this decision was not made lightly. No one feels the sadness of this decision more than the team.

As the strength and priority of Project Euler is the rich and challenging problem set it provides then we are pleased to be able to allow the problems to remain accessible. However, please note that full functionality of the website, including the ability to check answers, register, and login to existing accounts, remains disabled. Over time certain features may be reinstated, but currently there is no definite time frame which can be stated. In addition no new problems are likely to appear until the website is back up and running again.

(Friday 20 June 2014: Security Breach)