antivirus software

(redirected from Virus scanners)
Also found in: Medical, Financial.

antivirus software

[¦an·tē‚vī·rəs ′sȯf‚wer]
(computer science)
Software that is designed to protect against computer viruses.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

antivirus software

Programs to detect and remove computer viruses. The simplest kind scans executable files and boot blocks for a list of known viruses. Others are constantly active, attempting to detect the actions of general classes of viruses. antivirus software should always include a regular update service allowing it to keep up with the latest viruses as they are released.
This article is provided by FOLDOC - Free Online Dictionary of Computing (

antivirus program

Software that searches for viruses. Also known as a "virus scanner." As new viruses are discovered by the antivirus vendor, their binary patterns and behaviors are added to a database that is downloaded periodically to the user's antivirus program via the Web. Popular antivirus programs are Norton, McAfee, Sophos, Bitdefender, AVG and Kaspersky. Microsoft Defender is Microsoft's own antivirus software that comes with Windows, starting with Windows 8.

Antivirus programs are used on all Windows machines, but most Mac users do not install them. However, as more Macs are acquired, the Mac has slowly but surely become a target of attacks, and Mac antivirus programs are being installed at a more rapid rate than in the past. See virus, quarantine, disinfect and scareware.

Multiple Detection Approaches
Early antivirus scanning matched the binary signature (pattern) of executable files against a database of known malware signatures before they were allowed to run. This "scanning" process was vastly speeded up by doing a one-time scan of all the executables in the computer and also when a new one is installed. If the executable is virus free, a checksum (hash) of its binary pattern is computed and stored in a checksum database. The next time the executable is launched by the user, its checksum is recomputed and compared with the virus-free checksum. If they match, the file was not adulterated.

Because malware may generate a unique signature each time it is downloaded to an unsuspecting user, antivirus programs also use behavior detection, which looks for suspicious activities such as copying and deleting files when launched (see behavior detection). See Symantec, McAfee, Sophos, Bitdefender, AVG, checksum, virus, polymorphic virus and Reputation-based Security.

Scan and Create a Checksum (Hash)
This is commonly used to speed up antivirus scanning, because computing and comparing an executable's checksum is considerably faster than analyzing the file each time it is loaded.
Copyright © 1981-2019 by The Computer Language Company Inc. All Rights reserved. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction is strictly prohibited without permission from the publisher.
References in periodicals archive ?
The fact is that firewalls and virus scanners are not always sufficient on their own to guarantee all-around security for the network.
--Pop-up windows from virus scanners can obscure medical images and medically nec-essary alerts.
The tests performed by tine consulting company and solutions developerin.runs have indicated that every virus scanner currently on the market immediately revealed up to several highly critical vulnerabilities.
In addition, many virus scanners cannot detect newer rootkits.
They need to be protected by firewalls, virus scanners, anti-ad ware software, and pop-up blockers.
Recent Bagle variants tried to get around virus scanners by putting the executable into a password-protected Zip archive, with the password included in the e-mail's body text.
* Encrypted virus A virus using encryption to hide itself from virus scanners. That is, the encrypted virus jumbles up its program code to make it difficult to detect.
'Technical measures, such as virus scanners and filters, are an essential part of the solution, but they are not the only one.
Making it even more nefarious, SIRCAM hides itself in the infected user's Recycle Bin, where most virus scanners don't check.
Antivirus researchers recognized these patterns and optimized their virus scanners accordingly.
Use the latest version of any of the virus scanners listed below.