Editing Acid (computer virus)

{{Short description|Computer virus infecting .COM and .EXE files}}
{{No footnotes|date=March 2010}}
{{Infobox computer virus
 | Fullname                = Acid
 | Common name             = Acid 
 | Technical name          = Acid.674
 | Family                  = N/A
 | Aliases                 = Acid-670, Acid.670, Acid.670a, Avatar.Acid.670, Keeper.Acid.670
 | Classification          = [[Computer virus|Virus]]
 | Type                    = [[DOS]]
 | Subtype                 = [[COM file|COM]] and [[EXE]] infector
 | IsolationDate           = 1992
 | Isolation               = Unknown
 | Origin                  = Unknown
 | Author                  = Copyfright Corp-$MZU
}}

'''Acid''' is a [[computer virus]] which infects [[COM file|.COM]] and .[[EXE]] files including {{samp|[[command.com]]}}. Each time an infected file is executed, Acid infects all of the .EXE files in the current [[directory (file systems)|directory]]. Later, if an infected file is executed, it infects the .COM files in the current directory. Programs infected with Acid will have had the first 792 [[byte]]s of the host program overwritten with Acid's own code. There will be no file length increase unless the original host program was smaller than 792 bytes, in which case it will become 792 bytes in length. The program's date and time in the [[DOS]] disk directory listing will not be altered.

The following text [[Character string (computer science)|strings]] are found in infected files: 
*"*.EXE *.COM .."
*"Program too big to fit in memory"
*"Acid Virus"
*"Legalize [[LSD|ACiD]] and [[Cannabis|Pot]]"
*"By: Copyfright Corp-$MZU"

== External links ==
*[https://web.archive.org/web/20051215201857/http://www.probertencyclopaedia.com/L2.HTM Computer Viruses (A)], by Probert Encyclopedia
*[https://web.archive.org/web/20081011094026/http://vil.nai.com/vil/content/v_98138.htm Acid virus], by McAfee

[[Category:DOS file viruses]]