Mimail.H worm was found on 2nd of November, 2003. It is a close variant of Mimail.C worm. The description of Mimail.C worm variant can be found here:
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.
The Mimail.H worm is a minor variant of Mimail.C worm. The differences between these 2 versions are as follows:
1. The Mimail.H worm's file is 10784 bytes long, compressed with UPX file compressor, the unpacked file's size is 23072 bytes.
2. The worm installs itself to Windows folder as CNFRM33.EXE file and creates a startup key in the Registry:
[HKLM\Software\Microsoft\Windows\CurrentVersion\Run] "Cn323" = "%windir\cnfrm33.exe"
where %windir% is a Windows directory name.
3. The worm performs a DoS (Denial of Service) attack on the following sites:
spamhaus.org spews.org www.spamhaus.org www.spews.org
4. The worm spreads itself in the following message:
From: john@[domain of the recipient] Subject: don't be late! [some random characters] Body: Will meet tonight as we agreed, because on Wednesday I don't think I'll make it, so don't be late. And yes, by the way here is the file you asked for. It's all written there. See you. [some random characters] Attachment: readnow.zip
The attachment is a ZIP archive that contains the worm's executable file with READNOW.DOC.SCR name.
5. The .H worm variant doesn't have the spying functionality that was present in the .C worm variant.