MemScan

MemScan is a lightweight command line application that has the role of checking the working memory and detecting viruses that are specific to MS-DOS or boot malware. Using standard signatures and heuristic scanning techniques, the tool needs a minimal amount of free memory – 450 KB according to the developer – for its database and hash tables. The low amount can also be justified by the fact that it is adapted to work mostly in the network environments.

It is worth mentioning that the application can check different gates of the DOS memory, namely UNB and HMA. However, if you choose to scan the UNB for DOS versions 6 and Novell 7, then you are very likely to get a false alert. The developer states that the issues stems from the fact that a specific segment is occupied by COMMAND.COM loaded high. Consequently, it is recommended that you employ this option solely in case of emergency.

A noteworthy feature of the tool is the IVI option, which allows you to scan for over 180 of the most known MS-DOS viruses, including, but not limited to Plastique (AntiCad, Invader, Tobacco, 4.21, 5.21 and Cobol), 45 variants of the Yankee Doodle/Vacsina, Tequila, Tremor, 14 variants of Cascade and Yap as well as the stealth multipartite virus Hare.