Exploit:PHP/Preamble is a detection for a family of various PHP scripts. The scripts are used to test whether a particular site is vulnerable for a Remote File Inclusion (RFI) exploitation.
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.
An exploit is a short section of code that uses a vulnerability in an operating system or other software to run unauthorized code on target computers.
The scripts belonging to this family are usually used to test whether a site or a webpage is vulnerable to a Remote File Inclusion (RFI) vulnerability.
The scripts test various methods an attacker can use to introduce a malicious backdoor script onto the affected server.