Virus writers have created mobile phone malware that poses as a pirated copy of F-Secure's mobile anti-virus software. Skulls-L is a minor modification of the Skulls-C Trojan. Only the names have altered to leave the innocent at risk: Skulls-L unlike Skulls shares the same name as F-Secure's mobile anti-virus installation package, and the Trojan shows dialog text "F-Secure Antivirus protect you against the virus. And don`t forget to update this!"

Both viruses are capable of disabling the smartphone features of infected Symbian mobiles by deactivating messaging, net access and other apps. The malware replaces application icons with a picture of a skull, hence its name. F-Secure's mobile anti-virus is signed by Symbian - unlike Skulls Trojans - and the warning about missing installation package signatures should be a dead giveaway. Anecdotal evidence, however, suggests people get infected because they get fed up of saying "no" all the time little realising that if they got out of range of an infected device or turned off their phone they'd be quite safe.

F-Secure advises users to avoid downloading F-Secure anti-virus files from anywhere but its own server or the short link phoneav.com, which leads to the same site. ®

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