| ANTI | |
|---|---|
| Alias | ANTI-0, ANTI-A, ANTI-ANGE, ANTI-B, Anti-Variant |
| Type | Macintosh |
| Subtype | Application infector, copy protection |
| Classification | Virus |
| Isolation date | 1989-02 (ANTI-A), 1990-09 (ANTI-B) |
| Origin | France |
| Authors | Unknown |
| Technical details | |
| Platform | System 6 and older running Finder |
| Size | 1,352 bytes (ANTI-A), 1,152 bytes (ANTI-B) |
ANTI is a computer virus affecting Apple Macintosh computers running classic Mac OS versions up to System 6. It was the first Macintosh virus not to create additional resources within infected files; instead, it patches existing CODE resources.[1][2]
The most commonly encountered strains of ANTI have only subtle effects, and thus can exist and spread indefinitely without being noticed until an antivirus application is run.[3] Due to a bug in the virus, it cannot spread if MultiFinder is running, which prevents it from infecting System 7 and later versions of Mac OS as well as System 5 and 6 running MultiFinder.[1][4][5]