You may have a tough time filing your taxes this weekend.

The Canada Revenue Agency took its online services down Friday afternoon, after discovering an "internet vulnerability that affects some computer servers used by websites worldwide."

​"We are not aware of any unauthorized access to taxpayer information and we continue to monitor closely," said CRA spokesperson Patrick Samson in a statement Sunday.

"Digital services were taken offline as a precaution, not as the result of a successful hack or breach."

The CRA first took its website down as a precaution at midnight on March 10, said Samson. Parts of the site were still affected as of Sunday.

Samson said "action was taken" to protect web servers, and the website and digital services went back online an hour and a half later.

Later Friday afternoon, however, Samson said the CRA determined that while its website was protected, its digital services were "potentially vulnerable."

The CRA took its online services down at around 2 p.m. that day, and they remain offline nearly 48 hours later. The CRA website itself is still online.

In an earlier interview, Samson said digital services were taken down at 1 p.m., but later said that was incorrect.

An earlier message on the Canada Revenue Agency's website. The agency took its online services down Friday afternoon. (CRA)

Affected services include My Account, My Business Account, Represent a Client, the MyCRA mobile application, the MyBenefits mobile application, Netfile, EFILE and Auto-Fill My Return.

Samson said digital services will stay offline until the CRA determines there is no longer a security risk.

"The CRA takes the protection of Canadians' tax information very seriously," said Samson in the statement.

"The confidence and trust that individuals and businesses have in the CRA is a cornerstone of Canada's tax system."

No word on timeline

Speaking to CBC Saturday, CRA spokesperson Patrick Samson said he does not have information on when online services will be available again. He said the CRA is currently working as quickly as it can to resolve the issue.

"Taxpayers can still fill their tax forms, but they will have to wait before they can file," Samson said.

"We are doing everything in our power to establish services quickly."

Canadians are not currently able to access CRA's online services, which means they can't submit their taxes online. (Canada Revenue Agency)

CRA will notify people through social media when the online services are working again, he said.

Taxes for 2016 are due on or before April 30. However, because this date falls on a Sunday, CRA says it will consider returns filed on time if they are received by midnight on May 1, or postmarked May 1.

'A domino effect'

Michael Ford, president of the Ford Group Professional Corp. based in Newmarket, Ont., said the issue with the site prevents professional tax preparers and businesses like his from being able to e-file and do their jobs.

"When the site does hopefully come back up, we'll kind of have a domino effect," he said. "Even though it's still March and we've got until April 30, with a firm like ours that does over 500 tax returns, it hiccups our appointments and scheduling and it puts us in a rush situation."

Ford says his firm now has to reschedule appointments, which can be difficult for people who work during business hours. Not being able to file quickly also impacts low-income taxpayers more than those earning more.

"At this time of the year, low-income workers need their tax returns. They count on their tax returns and budget around that."

Statistics Canada's website is also unavailable. Samson said he is not aware of any connection between the problems.