Internet worms long thought to be dormant are spreading around the world after incubating in areas such as Latin America, where antivirus protection is less stringent.
Antivirus vendors are warning companies to make sure their software is up to date, after the discovery over the weekend of the internet worm Hybris which, like its fellow worm Navidad, has been upgraded as a risk.
Alex Shipp of MessageLabs, an application service provider that scans email to protect customers from viruses, said his company has intercepted 154 copies of Navidad and four of Hybris.
"Viruses like these bubble around in countries such as Brazil and others in South America, where protection is less good and antivirus measures are less rigorous, until they reach a large enough population to reach critical mass. They then spread quickly overseas," said Shipp.
Even though protection has been available for sometime, Navidad struck 10 of the Fortune 500 companies in the US last week, and has spread to the UK.
Hybris, which works only on Windows systems, spreads by attaching itself to infected emails. When a recipient executes the attached file, their PC becomes infected.
Moon's dark side is mountainous, rugged and never visible from the Earth
The groundwater basins in some areas of Tehran have been damaged irreversibly
This is the first time that any spacecraft on Mars has recorded air vibrations on the planet
Arctic sea ice is thickening at a faster rate during winter, thus slowing down long-term decline: NASA
But, the seasonal ice growth could only delay the demise of the Arctic ice cap for a few more decades