A new version of the Bagle computer virus started spreading on Monday among PCs connected to the Internet, and antivirus companies warned that more variants are sure to come.
The latest virus, called Bagle.AI by some antivirus companies and Beagle.AG by others, spreads through e-mail as an attached file, which infects a user"s PC when opened. The virus is extremely similar to previous versions of the program but uses a different form of compression as a way to dodge virus defenses.
"It really looks likes someone took the source code and changed a small number of things and then re-released it," said Oliver Friedrichs, senior manager for antivirus company Symantec"s security response team.
Symantec rated the virus as a three on its five-point scale, and rival McAfee called Bagle.AI a medium threat.