OSX.Leap.A arrives on the computer as an attachment to the following iChat Instant Message:
When the recipient clicks save, the archive file is saved as latestpics.tgz:
If the user opens the archive, the file latestpics is created:
Once OSX.Leap.A is executed, it performs the following actions:
- Displays the following message:
- Creates the following files:
- Deletes all files from the following folder:
- Copies /tmp/apphook to the following folder:
so that it runs every time an application starts.
- Uses Spotlight to search for the four most recently used applications this month, which do not require root permissions.
- Searches these files for the extended attribute oompa. If it does not find this attribute, it will infect the selected files.
- Infects the selected files by copying the contents of the data fork to the resource fork of the selected file, and then copying itself to the data fork of the selected file.
Note: Due to a bug in the code, the infected files may be corrupted and may not run correctly.
- Creates the extended attribute oompa and sets it to loompa.
- Monitors all launched applications. Every time the iChat application is launched, the worm sends the file latestpics.tgz to all the iChat contacts.
Note: Due to a bug in the code, the worm may corrupt the file so that it appears larger than it actually is, and it may not be sent successfully.
Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":