A crack is a copy of a computer program in which a copy protection provided by the manufacturer has been removed. Cracking is the activity of analyzing a computer program (usually by disassembling) in order to remove copy protection. A crack is a copyright infringement. Most commercial applications prohibit the modification of the software or the process of disassembly in their license terms. In the past, the cracked versions were often provided with an opening credits of a cracker group.
- License number crack (also: Key Generator or KeyMaker, or KeyGen for short) create a license number to activate a product. The programmer of the crack must have knowledge of original license numbers in order to be able to reprogram the algorithm. As a security measure, some software manufacturers rely on activation keys, where each valid license number must be activated additionally or, in the case of exclusively online applications, is checked every time it is started.
- No-CD/DVD, means that the target program, which would otherwise only run with the original CD/DVD, can also be started without it. For example, you can run games without a CD/DVD. For each version of the program, a different crack is usually necessary.
- Backup CD/DVD, means that the target program no longer queries the copy protection on the CD/DVD, but a CD/DVD is still required.
- Mini-backup images are tiny images of large CDs that are only designed to simulate existing copy protection. You have the advantage of being able to patch a program (game) at will without needing a crack.
Serials and keys are serial numbers or (CD) keys that are needed to install programs or to unlock advanced functions (e.g. shareware). These are often referred to as serialz. These can be calculated by license number cracks or read from memory (“serial fishing”). In this case, the program is stopped by means of a debugger at the point in the check routine where the correct serial number calculated by the program is compared with the one entered by the user.
In addition, many serial numbers were not obtained through reverse engineering, but through fraud against the software manufacturer or through unauthorized disclosure by a licensed user – these can be recognized by the fact that instead of cracker pseudonyms as licensees, real names or company names are included. Such serial numbers are not counted as cracks, as no reverse engineering is necessary to obtain them.
- Dongle emulations use a small program to simulate the alleged presence of a physical (USB) copy protection key (e.g. Syncrosoft, Ilok, CodeMeter) on which the license releases (via the Internet or pre-authorized) are contained.
- In the narrower sense, cracks are small files that exchange or modify files, especially in the case of software downloaded for testing purposes, in order to convert them into “full versions”. Since most manufacturers today offer free “trial versions” for download (shareware, demo versions), with which almost all functions can be tested extensively, the prospective buyer only has to download a few small files from the Internet to permanently activate the program; this is usually done immediately after payment. Some cracks are exact copies of these original files, others are written by crackers and manipulate the programs so that they can no longer update the program (“update”) (which allows the blocking of illegal versions) or permanently bypass product activation (a problem that Microsoft and Adobe in particular are exposed to), and the like. In most cases, complete libraries, which would otherwise be automatically added when shareware or demo programs are converted into fully usable full versions (downloading of purchase programs), are offered for download on relevant sites or in file-sharing exchanges. The same applies to serial numbers and key generators. They are also known as “crackz”.
Cracks are created by cracking groups. A distinction is made between release groups and web groups: Release groups tend to work in the shadows and use FTP servers to distribute their releases. Their aim is to be the first group to publish a crack for a program. For this purpose, a sophisticated dupecheck system is used, so that members of the group can check at any time for which program cracks are already available. Web groups publish their cracks on normal websites and thus make them accessible to a wide audience.
Cracks are often euphemistically referred to as patches, which is ambiguous in that patches actually fix a bug in the software and manufacturers often offer patches to their software.