A macro virus is a virus composed of a sequence of instructions that is interpreted rather than executed directly. • Macro viruses can infect either executables (Duff’s shell virus) or data files (Highland’s Lotus 1-2-3 spreadsheet virus). • Duff’s shell virus can execute on any system that can interpret the instructions
A logic bomb is a piece of code intentionally inserted into a software system that will set off a malicious function when specified conditions are met. For example, a programmer may hide a piece of code that starts deleting files (such as a salary database trigger ), should they ever be terminated from the company
Macro Viruses infect Word or Excel documents and templates, Lotus AmiPro templates and Access database macro objects. An example is the Melissa Word Virus. Companion Viruses have a name similar to that of an application, but instead of using the “.exe” file extension, it uses “.com.”
Multipartite Viruses infect the boot sector or Master Boot Record and also infect program files. A multipartite virus is a virus that can infect either boot sectors or executables. • Such a virus typically has two parts, one for each type. • When it infects an executable, it acts as an executable infector. • When it infects a boot sector, it works as a boot sector infector.
A virus may be encrypted to try to disguise itself and hide what it does For an encrypted virus to actually run, it has to decrypt its code and data - The portion that does this is referred to as a decryptor Encryption techniques can use random keys to make the virus code hard to spot -However the decryptor itself will have a signature
File Viruses infect program files and device drivers by attaching themselves to the program file or by inserting themselves into the program code.
A Trojan horse is a program that hides within or looks like a legitimate programs.
A Trojan horse is a program that hides within or looks like a legitimate programs.
The following is a partial list of available antivirus software solutions. Compare these to see which might meet the needs of your organization. Aladdin Knowledge Systems - http://www.esafe.com Frisk Software International - http://www.complex.is Alwil Software - http://www.avast.com Kaspersky Lab - http://www.kaspersky.com AVG Antivirus - http://www.grisoft.com McAfee - http://www.mcafee.com Central Command, Inc. - http://www.centralcommand.com Network Associates, Inc. - http://www.nai.com Command Software Systems, Inc. - http://www.commandcom.com Norman Data Defense Sys - http://www.norman.com Computer Associates International - http://www.cai.com Panda Software - http://www.pandasoftware.com Data Fellows Corporation - http://www.datafellows.com Proland Software - http://www.pspl.com Dr. Solomon's Software, Inc. - http://www.drsolomon.com Sophos - http://www.sophos.com ESET Software - http://www.mod32.com Symantec Corporation - http://www.symantec.com Finjan Software - http://www.finjan.com Trend Micro, Inc. - http://www.trendmicro.com
biometrics Traditionally, the science of measuring and analyzing human biological characteristics. In computer technology, biometrics relates to authentication and security techniques that rely on measurable, individual biological stamps to recognize or verify an individual’s identity. For example, fingerprints, handprints, or voice-recognition might be used to enable access to a computer, to a room, or to an electronic commerce account. Security schemes are generally categorized into three levels: level 1 relies on something the person carries, such as an ID badge with a photo or a computer cardkey; level 2 relies on something the person knows, such as a password or a code number; level 3, the highest level, relies on something that is a part of the person’s biological makeup or behavior, such as a fingerprint, the pattern of blood vessels in a retina, or a signature. See also voice recognition, fingerprint reader, handwriting recognition (definition 1).
Methods of hiding the existence of a message or other data. This is different than cryptography, which hides the meaning of a message but does not hide the message itself.
Stegnography - refers to hiding information in ways that prevent the detection of hidden messages used to communicate information without letting others even notice that a communication is being taken place
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