This is not a trojan or a virus. Nastysex is a program to show pornographic images. We sometimes get queries about it, as it can easily cause substantial phone costs.
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 detection database 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.
The program is distributed in several different version from a wide range of XXX web sites. Filenames include SEXWARE.EXE and XXXFILES.EXE.
When installing the software, it explains that the software is going to call out with a modem to download pornographics pictures "from another country" as they are "too explicit to be stored in USA".
The user has a free choice to decline the offer. If he does, he gets this display:
If the user enters his user info and his modem's COM port, the software will call out to Guyana in Southern America (phone number: +592 279 156) and will download XXX pictures.
Although this can easily cause huge phone bills, the program does not try to hide the fact that it's going to call to another country. Thus, this is not a trojan and F-Secure Anti-Virus WILL NOT detect or stop this program.
[Mikko Hypponen, F-Secure]