More than 600,000 Mac Computer have been infected with a new version of the Flashback Trojan horse a Java exploits.
The malware installs itself if a user visits a malicious website, exposing the computer to control by hackers.
Apple has released a fresh Java update that it says removes the Flashback Trojan on infected Macintosh computers.
Security firm, Kaspersky, has recalled its own Flashback Trojan-removal tool,Symantec another security company did the same and released Norton Antivirus 12 for Mac.
Kaspersky Lab has successfully fixed its free Kaspersky Flashfake Removal Tool. A bug was identified in the original version of the tool, which was first reported at approximately 17:40 MSK (GMT+4) on April 12. The tool was taken offline for maintenance.