Summary
Graps worm was discovered in the beginning of July 2003. This worm spreads in local networks. It scans a network for vulnerable computers and tries to get access the IPC$ and ADMIN$ shares by performing a dictionary attack (using a set of pre-defined weak passwords to get access). If the worm succeeds, it copies itself to remote computer, activates its file and deletes IPC$ and ADMIN$ shares.
Removal
To disinfect a system it's enough to delete mwd.exe file and 3 above mentioned batch files from a hard disk.
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
The worm is a 53kb Windows PE executable file written in Visual Basic and compressed with UPX file compressor. The worm spreads itself with the help of the following files:
psexec.exe - a utility that allows to run processes on remote computers mswinsck.ocx - standard WinSock library for VB applications wds.bat \ wds2.bat - batch files that spread the worm to remote computers (dropped by the worm) wds3.bat / mwd.exe - the worm's executable file
The batch scripts that the worm drop are used to get access to IPC$ and ADMIN$ share protected by a weak password or no password at all. When such a share is discovered, the scripts copy the worm's main file mwd.exe and also psexec.exe and mswinsck.ocx files to \ADMIN$\System32\ folder (which is a Windows System folder on a remote computer) and start the worm's file remotely with psexec.exe utility. As a result a remote computer becomes infected with the worm. After spreading the worm tries to delete IPC$ and ADMIN$ shares.
On an infected computer the worm creates a startup key for its file in System Registry:
[HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run] "Windows Management Instumentation" = "%winsysdir%\mwd.exe"
The worm has a few additional features. It listens to the specific port and can allow remote hackers to log into it and perform the following actions:
- perform DoS (Denial of Service) attack - get system information - search for specified files on a hard disk - redirect traffic (works as a proxy) - scan for open ports
Protect your devices from malware with F‑Secure Total
Protecting your devices from malicious software is essential for maintaining online security. F‑Secure Total makes this easy, helping you to secure your devices in a brilliantly simple way.
Award‑winning antivirus and malware protection
Online browsing, banking, and shopping protection
24/7 online identity and data breach monitoring
Unlimited VPN service to safeguard your privacy
Password manager with private data protection
Choose how many devices you want to protect to get started.
Free customer support
Cancel anytime
The trial does not obligate you to buy the product
After 30 days your subscription will renew automatically for one year at €69.99.
)
)
More Support
Community
Ask questions in our Community.
User guides
Check the user guide for instructions.
Contact Support
Chat with with or call an agent.
Submit a Sample
Submit a file or URL for analysis.