Classification

Category :

Malware

Type :

Virus

Aliases :

PHX

Summary

This virus is quite common in South America, but isolated reports have been received from Northern Europe as well.

Removal

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.

Technical Details

PHX stays resident in memory and infects COM and EXE programs when they are executed.

When PHX is infecting a file, it calls it by a name that has the "!" character appended to the end of the name, ie. FILE.EXE is called by the name FILE.EXE!, which works as well. This is done in order to by-pass some behaviour blockers that monitor access to files with executable extensions.

PHX alters one field in CMOS memory, and might cause CMOS corruption. The virus will also sometimes corrupt disk writes. This happens only when several conditions are met. These conditions include that an environment variable beginning with "PHX" is present, a certain INT call is made from within a certain type of program code and that an IN to port 03E4h returns anything else except the value FFh.

The activation routines are directed against applications written by a specific person and company.