ZY

Virus Name: Zy

Virus Type: File Infector Virus (infects .COM files)

Virus Length: 463 Bytes(COM)

PC Vectors Hooked: None

Executing Procedure:
1) Searches for and infects one uninfected .COM file in the current directory.
2) It finally executes the originally called file.

Damage: None

Detecting Method:
1)Infected files will increase by 463 Bytes.

Note:
1) Doesn't stay resident in memory.
2) ZY doesn't hook INT 24h when infecting files. Error message occurs if there is an I/O error (such as write protect).


Zeppelin

Virus Name: ZEPPELIN

Virus Type: File Infector Virus (infects .COM & .EXE files)

Virus Length: 1508 Bytes(COM & EXE)

PC Vectors Hooked: INT 24h

Executing Procedure:
1) Searches for and infects 4 uninfected .EXE or .COM files in the current directory.
2) It then shows a lot of uncertain codes, makes sounds, and then the system halts.

Detecting Method:
1)Infected files will increase by 1508 Bytes.
2) A lot of codes appear on the screen.

Note:
1) Doesn't stay resident in memory.
2) Zeppelin hooks INT 24h when infecting files. Omits an I/O error (such as write protect).


Zz1

Virus Name: Zz1

Virus Type: Overwrite, COM File infector

Virus Length: 127 bytes

Executing Procedure:
1) Searches for an uninfected COM file on the current directory and infects it (Infects only one file at a time).
2) If there is not an infectable file, it changes data in system RAM to set screen lines to 81. This confuses the screen.

Damage:
1) It overwrites first 127 bytes of original files by virus code. Original files are destroyed.
2) Confuses screen if there are no infectable files.

Note: Date and time of infected files do not change.