President George W. Bush's computer security advisor wants people to keep hacking for the good of the country.
Speaking at the Black Hat conference in Las Vegas this week, Richard Clarke said that top security professionals and hackers needed to keep cracking away at faulty computer code.
He said that software makers were unable to find the majority of glitches and security holes in software and it was up to end-users to find them.
Hackers and security pros "have an obligation to find the vulnerabilities" in software systems - and to work with software makers to patch them up, he said.
But he did not think that hackers should go public with their finds straightaway. Instead they should get touch with software makers first.
"If the companies don't respond, they should contact the government," he added.
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