The history of viruses and computer security is interesting and dynamic, starting with geeky pranksters and evolving into a multi-billion dollar business. Fortunately (whether by design or destiny), Macintosh viruses have been noticeably missing. And while the threats for Mac are few and far between, they re not completely nonexistent. Some of the earliest known viruses started on Mac computers and new malware still pop up every now and then, even for Mac OS X.

Following is a brief visual history and timeline of the most significant Macintosh viruses. While (thankfully) not as epic as the volumes of PC viruses, the history of Mac viruses is an exciting chapter, complete with unexpected twists, self-replicating elk, random pickles and even hit dance songs from the '90s.

Mac Viruses Timeline showing the history of Macintosh viruses.


 1982: 15-year-old Rich Skrenta creates the first known Macintosh viruses to go wild, Elk Cloner. The boot sector virus spreads itself on Apple II computers via infected floppy disk, and results in a short poem showing up every 50th boot.

1994: The short-lived INIT-29-B virus modifies system files and other applications, sometimes crashing the system.

1995: The HyperCard HC-9507 virus puts Mac users in a  pickle  by spreading to other HyperCard stacks.

1998: The  Hong Kong virus  (actually a worm called AutoStart 9805) uses the AutoPlay feature of QuickTime to infect PowerPCs by copying itself across disk partitions.

2006: The OSX/Leap-A (aka OSX.Oomp) worm spreads through the iChat buddy lists by sharing the file latestpics.tgz file (falsely advertised as leaked screenshots of the new OS 10.5 Leopard).

2006: The proof of concept virus OSX.Macarena poses no threat, but can infect files in the current folder of Intel-based Macs.

2008: The Trojan horse AppleScript.THT takes advantage of vulnerability in the Remote Desktop Agent feature, hides itself from the firewall and allows hackers to take control of the infected computer.

2008: The OSX.Lamzev.A and OSX.TrojanKit.Malez Trojan horses are created to open a back door. Fortunately, a hacker would pretty much have to have control of your Mac already to use it.

2008: Masquerading as a video codec on adult websites (always a tip-off), the OSX.RSPlug.D Trojan allows a remote server to download files.

2009: Illegally downloaded copies of the popular software iWork  09 and Adobe Photoshop CS4 come with the malicious OSX.Iservice and OSX.Iservice.B Trojans used to steal users passwords in attempts to create iBotNet.

2010: A new iteration of the Trojan horse OSX/HellRTS threatens to duplicate itself and open a backdoor for hackers.

2011: Rogue antivirus program (aka "scareware") MACDefender attempts to convince users to install the fake Mac security software, which then pushes porn popups to encourage you to purchase the software to "fix" the problem.

While the risk isn t nearly as prevalent on the Mac landscape, the threat of Macintosh viruses is real. Luckily, there are professional security solutions available, including Mac antivirus software. Our reviews and articles on Macintosh antivirus, virus scan, virus protection and more will help you learn the features and benefits of the best Mac antivirus software.

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