Backdoor:OSX/Iworm

Classification

Category :

Malware

Type :

Backdoor

Aliases :

Backdoor:OSX/Iworm.A, Trojan-Dropper:OSX/Iworm.A , Mac.BackDoor.iWorm, Mac.OSX.iWorm

Summary

Backdoor:OSX/Iworm connects affected Mac OS X machines to a botnet and is capable of a executing a range of commands. At the time of writing, there have been no reports of the IWorm botnet being used for malicious activities.

Removal

The F-Secure security product will automatically remove the file.

A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:

  • Check for the latest database updates

    First check if your F-Secure security program is using the latest updates, then try scanning the file again.

  • Submit a sample

    After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.

    Note: If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.

  • Exclude a file from further scanning

    If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.

    Note: You need administrative rights to change the settings.

Technical Details

Backdoor:OSX/Iworm is reportedly spread via pirated software downloads. Once present on a machine running the Mac OS X operating system, the malware installs a file in the Library directory and then connects to Reddit's search page.

An unusual feature of this malware and the botnet it connects to is that a specific subreddit was used to distribute the IP addresses of the botnet's command and control (C&C) servers to affected machines. The subreddit has since been cleared of this C&C-related data, and the account used to post the data was shut down.

If the affected machine does successfully connect to the botnet, it is able to carry out a range of instructions, including downloading a file, executing a system instruction and changing its own configuration file. At the time of writing, there have been no reports of the IWorm botnet being used for malicious activities.

Following public reports of the malware, Apple updated OS X's built-in XProtect component to include identification for this malware.