Overview
This lecture covers the recommended steps for malware removal from a computer system, highlighting both practical removal strategies and best practices for prevention and recovery.
When to Use Manual Malware Removal
- Organizations typically prefer deleting and reimaging infected systems to ensure all malware is removed.
- Manual malware removal is used mainly to recover important files before wiping the system.
Identifying Malware Infection
- Obvious symptoms include virus warning messages or alerts from security software.
- Subtle symptoms can be slow system performance, odd application errors, or unusual behavior.
- Additional research is advised when symptoms are unclear.
Initial Response to Malware
- Immediately quarantine the system by disconnecting from the network to prevent malware spread.
- Avoid backing up infected systems, as this can preserve the malware.
System Restore Considerations
- Malware often infects Windows Restore Points, making system restore an unreliable removal method.
- Disable system restore to delete infected restore points before proceeding.
Removing Malware
- Delete clearly identified malicious files using anti-malware software.
- Ensure antivirus engine and signature definitions are fully updated before scanning.
- Update antivirus manually if malware blocks automatic updates, possibly using another system and USB.
- Use Safe Mode or the Windows Pre-installation Environment (WinPE) if malware affects normal booting.
- Repair boot records if necessary to regain file system access.
Recovering and Reimaging
- Once files are recovered, perform a full wipe and reimage or reinstall the system using a clean image.
- This restores the operating system, drivers, and applications quickly and safely.
Post-Removal Configuration
- Enable real-time and periodic antivirus scans.
- Schedule automatic antivirus and OS updates.
- Re-enable and configure system restore, then create a new restore point.
User Education and Best Practices
- Train users on safe computing habits and how to respond to suspicious activity.
- Use posters, message boards, login messages, or intranet pages to communicate security tips.
Key Terms & Definitions
- Malware — Malicious software designed to harm or exploit computer systems.
- Quarantine — Isolating an infected system to prevent malware spread.
- System Restore — Windows feature for returning a system to a previous state.
- Reimage — Wiping a system and installing a fresh, clean operating system image.
- Signature Definitions — Antivirus database files that identify malware.
Action Items / Next Steps
- Practice malware removal steps on a test system.
- Review antivirus and update configuration on your own computers.
- Prepare or review user awareness materials about malware prevention.