malwareanti-malware-160630191004 (1).pdf
- 1. MALWARE & ANTI-MALWARE BY: ARPIT MITTAL
- 2. CONTENTS MALWARE PURPOSE OF MALWARES TYPES OF MALWARE VIRUSES, WORMS, TROJANS HOW MALWARE SPREADS
- 3. What is Malware? Program or code • Made up of two words “Malicious” + “Software”. • 'Malware' is an umbrella term used to refer to a variety of forms of hostile or intrusive software, including • viruses, worms, trojan horses, spyware, adware etc.
- 4. The purpose of Malware • To subject the user to advertising
- 5. The purpose of Malware • To launch DDoS on another service
- 6. The purpose of Malware • To spread spam. • To commit fraud, such as identity theft • For kicks (vandalism), and to spread FUD (fear, uncertainty, doubt) • . . . and perhaps other reasons
- 8. But we willbediscussing…. MALWARE WORMS VIRUSES TROJAN HORSES
- 9. What exactly is a Virus? Virus propagates by infecting other programs • It attaches itself to other programs or file. • But to propagate a human has to run an infected program. • A term mistakenly applied to trojans and worms. • Self-propagating viruses are often called worms
- 10. • Many propagation methods • Insert a copy into every executable (.COM, .EXE) • Insert a copy into boot sectors of disks • Infect common OS routines, stay in memory
- 11. First Virus: Creeper Written in 1971 Infected DEC PDP-10 machines running TENEX OS Jumped from machine to machine over ARPANET copied its state over, tried to delete old copy Payload: displayed a message “I’m the creeper, catch me if you can!” Later, Reaper was written to hunt down Creeper
- 12. Types of Viruses Parasitic Virus - attaches itself to executable files as part of their code. Runs whenever the host program runs. Memory-resident Virus - Lodges in main memory as part of the residual operating system. Boot Sector Virus - infects the boot sector of a disk, and spreads when the operating system boots up (original DOS viruses). Stealth Virus - explicitly designed to hide from Virus Scanning programs. Polymorphic - Virus - mutates with every new host to prevent signature detection.
- 13. Virus Phases Dormant - waits for a trigger to start replicating Propagation - copies itself into other programs of the same type on a computer. Spreads when the user shares a file with another computer. Usually searches a file for it’s own signature before infecting. Triggering - starts delivering payload. Sometimes triggered on a certain date, or after a certain time after infection. Execution - payload function is done. Perhaps it put a funny message on the screen, or wiped the hard disk clean. It may become start the first phase over again.
- 14. Okay, So Then What’s a Worm? Similar to a virus, but propagates itself without human interaction.
- 15. Six Components of Worms 1) Reconnaissance 2) Specific Attacks 3) Command Interface 4) Communication Mechanisms 5) Intelligence Capabilities 6) Unused and Non-attack Capabilities
- 16. Reconnaissance • Target identification • Active methods • scanning • Passive methods • OS fingerprinting • traffic analysis
- 17. Specific Attacks • Exploits • buffer overflows, cgi-bin, etc. • Trojan horse injections • Limited in targets • Two components • local, remote
- 18. Command Interface • Interface to compromised system • administrative shell • network client • Accepts instructions • person • other worm node
- 19. communications Information transfer Protocols Stealth concerns
- 20. Intelligence Database Knowledge of other nodes Concrete vs. abstract Complete vs. incomplete
- 21. Worm Propagation Back-Chaining Propagation The Cheese worm is an example of this type of propagation where the attacking computer initiates a file transfer to the victim computer. After initiation, the attacking computer can then send files and any payload over to the victim without intervention. Then the victim becomes the attacking computer in the next cycle with a new victim. This method of propagation is more reliable then central source because central source data can be cut off.
- 22. Worm Propagation Central Source Propagation This type of propagation involves a central location where after a computer is infected it locates a source where it can get code to copy into the compromised computer then after it infects the current computer it finds the next computer and then everything starts over again. And example of the this kind of worm is the 1i0n worm.
- 23. Worm Propagation Autonomous Propagation Autonomous worms attack the victim computer and insert the attack instructions directly into the processing space of the victim computer which results in the next attack cycle to initiate without any additional file transfer. Code Red is an example of this type of worm. The original Morris worm of 1988 was of this nature as well.
- 24. Yeah, but what’s a Trojan? A small program that is designed to appear desirable but is in fact malicious Must be run by the user Do not replicate themselves Used to take over a computer, or steal/delete data Good Trojans will not: alert the user alter the way their computer works
- 25. TROJANS Trojan Horses can install backdoors, perform malicious scanning, monitor system logins and other malicious activities. Majority of modern trojan horses are backdoor utilities Sub Seven Netbus Back Orifice Feature set usually includes remote control, desktop viewing, http/ftp server, file sharing, password collecting, port redirection Some of these trojan horses can be used as legitimate remote administration tools Other trojans are mostly programs that steal/delete data or can drop viruses
- 26. HOW MALWARE SPREADS… Just by visiting seemingly harmless website. DRIVE BY DOWNLOAD. By mails, attachments, links. By physical media. Software vulnerabilities or bugs.
- 27. Anti-MALWARE
- 28. ANTI-MALWARE Softwares developed to combat all types of Malwares. Are they different from Anti-Viruses? Viruses were extremely “popular” in the ‘90s, which is when the term “Antivirus” became common. but today viruses are the minority when it comes to malware. So, nearly all anti-virus provides security from most of the malwares.
- 29. So the difference… ANTI-VIRUS usually deals with the older, more established threats, such as Trojans, viruses, and worms protects users from lingering, predictable-yet-still-dangerous malware. best at crushing malware you might contract from a traditional source, like a USB or an email attachment ANTI-MALWARE typically focuses on newer stuff, such as polymorphic malware and malware delivered by zero-day exploits protects users from the latest, currently in the wild, and even more dangerous threats. updates its rules faster than antivirus, meaning that it's the best protection against new malware you might encounter while surfing the net
- 30. Effective Anti-Malware Strategy Core Product Research Team Update infrastructure
- 31. Anti-Malware Engine Scanning • Monitor and examines various locations on computer like hard disk, registry. • If change has been made to a critical component, it could be sign of infection Detection • Matching with the definition list. • Classifying as appropriate type such as virus, spyware or Trojans. Removal
- 33. Common challenges… RootKits • Program that can hide files, registry entries, network traffic, or other information. • Kernel mode rootkit could tamper with operating system at lowest level. Blended Threats • Combined characteristics of viruses, worms and spyware. Performance • Maintaining high level performance on machine is critical. Classification • Understand the nature of threat. • Wide variety of nature and context make it difficult to manage.
- 34. Two Approaches of Scanning 1.Specific Scanning • signature detection • the application scans files to look for known viruses matching definitions in a “dictionary”. • after recognizing the malicious software the antivirus software can take one of the following actions: 1. attempt to repair the file by removing the virus itself from the file. 2. quarantine the file. 3. or delete the file completely.
- 35. Generic Scanning Generic scanning is also referred to as the suspicious behavior approach. Used when new malware appear. In this method the software does not look for a specific signature but instead monitors the behavior of all applications. if anything questionable is found by the software the application is quarantined and a warning is broadcasted to the user about what the program may be trying to do.
- 36. Generic Scanning if the software is found to be a virus the user can send it to a virus vendor researchers examine it, determine its signature, name and catalogue it and release antivirus software to stop its spread.
- 37. Two Other Approaches Heuristic analysis another form of generic scanning The sandbox method
- 38. Heuristic Analysis software tries to emulate the beginning of the code of each new executable that the system invokes before transferring control to that executable. if the program attempts to use self-modifying code or appears to be a virus, it’s assumed the virus has infected the executable. there are many false positives in this approach.
- 39. Sandboxing in this approach an antivirus program will take suspicious code and run it in a “virtual machine” to see the purpose of the code and exactly how the code works. after the program is terminated the software analyzes the sandbox for any changes, which might indicate a virus.