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>that is, it infects and spreads without user interaction My understanding was that viruses that spread without interaction are called worms. Both trojans and

by ginko 6y ago

>that is, it infects and spreads without user interaction My understanding was that viruses that spread without interaction are called worms. Both trojans and worms are viruses.

charonn0 6y ago
The terminology is based on how the malware spreads. Worms actively exploit holes in network programs (e.g. emailing themselves to your contacts), trojans disguise themselves as something useful (e.g. a pirated game). True viruses spread by injecting copies of themselves into innocent files in such a way that opening the file triggers the payload. True viruses are rare these days because the infection vector is passive and relatively slow: an infected file must be transferred by user action to another computer, for example by sharing an infected file via floppy disk.
- sandworm101 6y ago
  >> for example by sharing an infected file via floppy disk. Or an "excel" file attached to an email or posted in a chat group that is execute by the host automatically and inserts itself somewhere. Viruses remain alive and well online.
kazinator 6y ago
False. There were viruses in the PC and Mac world for years, long before the 1988 Morris worm incident popularized the "worm" term. Viruses spread via interactions like booting an infected floppy disc, or running an infected program copied from another user. A virus is simply a piece of malicious code which attaches itself to programs, arranges for itself to be executed when those programs to be run, and thereby spreads to more programs as programs are copied from system to system by unsuspecting users. A Trojan horse is a malicious program which a user is somehow fooled into trusting, installing and running. It doesn't have to be a virus at all; for instance, it could be a fake authentication dialog that steals their credentials and then defers to the real authentication. A malicious thumb drive deliberately dropped in the parking lot of a company is a modern example of a Trojan horse. It might not infect anything, just steal information and transmit it.

by ginko 6y ago

>that is, it infects and spreads without user interaction My understanding was that viruses that spread without interaction are called worms. Both trojans and worms are viruses.

charonn0 6y ago

The terminology is based on how the malware spreads. Worms actively exploit holes in network programs (e.g. emailing themselves to your contacts), trojans disguise themselves as something useful (e.g. a pirated game). True viruses spread by injecting copies of themselves into innocent files in such a way that opening the file triggers the payload. True viruses are rare these days because the infection vector is passive and relatively slow: an infected file must be transferred by user action to another computer, for example by sharing an infected file via floppy disk.

sandworm101 6y ago
>> for example by sharing an infected file via floppy disk. Or an "excel" file attached to an email or posted in a chat group that is execute by the host automatically and inserts itself somewhere. Viruses remain alive and well online.

kazinator 6y ago

False. There were viruses in the PC and Mac world for years, long before the 1988 Morris worm incident popularized the "worm" term. Viruses spread via interactions like booting an infected floppy disc, or running an infected program copied from another user. A virus is simply a piece of malicious code which attaches itself to programs, arranges for itself to be executed when those programs to be run, and thereby spreads to more programs as programs are copied from system to system by unsuspecting users. A Trojan horse is a malicious program which a user is somehow fooled into trusting, installing and running. It doesn't have to be a virus at all; for instance, it could be a fake authentication dialog that steals their credentials and then defers to the real authentication. A malicious thumb drive deliberately dropped in the parking lot of a company is a modern example of a Trojan horse. It might not infect anything, just steal information and transmit it.