Symantec has patched the widely reported flaw in the English versions of its corporate antivirus software.

The serious flaw affects recent versions of its Client Security and Antivirus Corporate Edition and could be exploited by hackers to run unauthorised software on unpatched PCs.

It was discovered by rival security vendor eEye Digital Security and first disclosed last Wednesday. Three days later, Symantec patched the problem, according to an alert published on its website.

The patches are for English language versions of Symantec's products only, and a Symantec spokesman could not say when the complete range would be patched.

Symantec did not release many details on the flaw, but eEye has warned that it is the kind of vulnerability that could be used to build a self-replicating worm attack, similar to the Blaster and Slammer outbreaks of 2003.

That has not happened to date, and Symantec is "not aware of any customers impacted by this vulnerability, or of any exploits of this vulnerability," the alert said.

The problem affects version 3.0 and above of Client Security, and version 10 and above of Antivirus Corporate Edition. Symantec's Norton line of consumer antivirus products are not affected.