The agency says last week's hacking drew attention to vulnerabilities on its public website but it never penetrated the internal servers that hold more sensitive data.
A German hacker said he discovered that the official websites of the Canadian Space Agency and the European Space Agency were flawed.
He said the Canadian Space Agency's site had a security hole that could be exploited in many ways by ill-intentioned hackers.
The hacker (known as D35m0nd142) said on the Softpedia website that he didn't cause any damage to the databases and the sites' administrators were notified immediately.
The CSA says the vulnerability was found on a page of astronautic vocabulary that allowed users to obtain the definition of terms used in the field.
In an email to the Canadian Press, the space agency says it took immediate action to correct the problem and is evaluating if other applications are at risk and will correct any issues that arise.
The news came just days after the SecurityNewsDaily website reported that a laptop stolen from NASA last year was unencrypted and contained command and control codes for the International Space Station on it.
It says the American space agency's inspector general made the revelation in testimony before a United States House subcommittee last week.
A NASA public-affairs officer insisted that at no point were operations of the International Space Station in jeopardy because of a data breach.
And the Canadian agency says that, like all websites, its corporate page is vulnerable to such attacks.
But it says the Canadian Space Agency's website is isolated and the incident did not touch its internal network.