Trojan:SymbOS/Appdisabler.A is a malicious SIS file dropper, which is dropped by the Skulls.J trojan.
Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.
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.
Appdisabler.A tries to disable third party file managers and drops two other malwares:
When installed, AppDisabler.A will replace many third-party file managers as well as other third party applications with non-functional application files. It also drops Locknut.B and Cabir.Y onto the system.
When active, Appdisabler.A disables following applications:
The dropped malware Cabir.Y will not start automatically, but will attempt to start at the next boot. However, on most devices Locknut.B will cause application loading to fail. This prevent Cabir.Y from starting.
Appdisabler.A also contains a bootstrap component that attempts to start a component of Skulls.J showing animation of flashing skull. This functionality is also hampered by Locknut.B.