What's a marijuana virus?

The cannabis virus is also called New Zealand virus, because in early 1988, Wellington in New Zealand reported the discovery of the cannabis virus. The marijuana virus only infects 360KB of floppy disks and does not infect hard drives. Later cannabis varieties, most of them infected with the hard drive, and some also changed the display information, and some of the information before the display statement to judge the conditions before the virus is on the screen to display the following string: yourpcisnowstoned! legalisemarijuana! instead of the original design displays this information when the system clock counter is recorded in multiples of 8.

Source

The name of the marijuana virus is a piece of information from the virus's body, and there are several variants of the current marijuana virus.

Harm

The marijuana virus is short, a total of less than 400 bytes of code completes the resident memory, modifies the interrupt vector, distinguishes the soft hard drive, infects the floppy disk, infects the hard disk, directs the original hard drive main boot sector, displays the timing judgment, displays the information as well as the Hemp virus infection sign judgment to prevent the duplicate infection and so on many

Characteristics

Around 1989, the cannabis virus was introduced into China, becoming a major virus that spread around the time. Like many other boot-zone viruses, the infection of a floppy disk does not determine whether the floppy disk contains a DOS system file, regardless of whether the floppy disk is a bootable system disk, resulting in not only the system disk being infected, but the general data disk being infected. When a floppy disk with a marijuana virus is inserted in a: drive, the first attempt to read a: disk when the system restarts. As long as the boot sector content of the floppy disk is read into the PC, and even if the boot is unsuccessful, marijuana is already in memory and can continue to infect the hard drive and his virus-less floppy disk. PC will be hidden in the floppy boot sector of the virus read into memory is just a moment of things, often in the user realized that they started the PC in the wrong floppy disk, or should not be in the floppy disk drive, it is too late. Many kinds of lead-zone poison is infected by this way into the hard drive. PC hard disk is inherently non-toxic, because of an accidental operation, so that the pilot zone virus from the floppy transmission into the hard drive, which is a lot of users have experienced. After analysis, we know that the cannabis virus, like many other boot-zone viruses, can only be transmitted from a floppy disk to the hard drive.

Infection mode

In the form of infection, the cannabis virus is transmitted when the system performs a read operation. Because the disk read and write interrupt is taken over by the cannabis virus, any disk operation is filtered by it, and the reading disk is the most common operation, and the cannabis virus, when it is judged that a read operation occurs, invokes the infection subroutine to infect those disks that have not been infected by the cannabis virus. The hallmark of the diagnosis is the cannabis virus's own launcher code, making it difficult for the correct boot sector initiation program to produce the immune marker for the marijuana virus. Here we can also see that it is impossible to produce an immune marker that can be used as a variety of viruses. We can not rely on the production of immune marker methods to protect against computer viruses.

As a marijuana virus program itself, its internal does not deliberately write the destruction code, such as Fat Qing 0, formatted disk, etc., can not be classified as a vicious virus, but in fact, the cannabis virus can lead to data confusion, file loss and so on.

For floppy disks, the cannabis virus moves the original DOS boot sector to 0, 1, 3 sectors, and the contents of the original sector are overwritten. If the sector contains useful information, this will cause loss in 360KB capacity of floppy disk, this sector is the last sector of the directory area, if the root directory of the number of files is not a lot, will not use this sector, there will be no impact on the 1 2MB capacity of the floppy disk, The cannabis virus occupies the sector in the third sector of the directory area, not the last sector, when all 16 files stored in the sector are lost and 32 files in the first two sectors of the root directory are not touched. After sector 3rd of the sector is destroyed by the third sector, the files stored in it cannot be found. This is where the cannabis virus covers the normal sector. Conversely, if the disk is a system boot disk, after being infected with marijuana, the original boot fan is written to 0 tracks, 1 cylinders, 3 sectors, and when the number of files created on the disk increases gradually, overwriting the original boot sector content that occupies the directory area, the disk is turned into an bootable boot disk by the bootable boot disk.

For hard disks, the marijuana virus may not cause any damage or damage data, depending on the DOS version number installed on the disk. When the hard disk partitions, there is a reserved area, also known as the hidden area. DOS2 x's fdisk partition, the number of sectors in the hidden area is O, when the cannabis virus infects the hard drive, it moves the original boot sector to the 0-side 7 Sector of O Road, which happens to be the fat sector of the hard disk C: partition. In this case, the loss of data is not caused by a corrupted fat, or the primary boot zone that occupies the location is corrupted, causing the hard drive to fail to start. DOS3) x's fdisk delimits the entire track as a hidden area, except that the first sector where the primary boot sector is used is useful, and other sectors are reserved for DOS information. In this case, even if the hard drive is infected with a marijuana virus, the data in the system is not damaged because 0 0-face 7 sectors are the sectors in the reserved area.

In memory, the cannabis virus takes up 2KB of memory and actually takes up only 1KB. Check the marijuana virus, to be in the memory without viruses, or just clear off the virus and will soon be infected.