How Are Computer Games ‘Cracked’?

Computer games are “cracked” by finding ways to bypass the security checks made by the company. This can be done by hex-reading, hex-editing, debugging, or using a keygen.

In 2012, Ubisoft’s CEO, Yves Guillemot, claimed that PC gaming had a piracy rate of 93% to 95%. This widespread piracy results in significant losses for gaming companies.

Torrent websites play a significant role in facilitating piracy despite facing litigation. These websites distribute pirated software that often includes a “crack” that allows users to bypass the security checks imposed by the game’s manufacturer and play the game for free.

Cracking games requires no special software knowledge, as the process is usually straightforward and only takes a few clicks. This ease of cracking can make individuals feel like hackers. Before delving into the methods of cracking games, it’s essential to understand the tools used to accomplish this.

What Does It Mean For A Game To Be ‘Cracked’?

When people say a game has been “cracked,” they mean that someone has modified it so it runs without the copy protection the publisher built in. A retail game normally checks whether you own a legitimate copy, by asking for a serial key, phoning home to a server, or verifying a license file before it will start. A crack is a small program or modified game file that disables, bypasses, or fools that check, so the game launches as though it had been paid for. The end result is a “cracked game”: a copy that runs for free.

A crack is not the same thing as a keygen (a tool that manufactures a valid-looking serial key) or a simple patch (an official update from the developer). All three change how the software behaves, but a crack’s specific job is to remove the lock. Cracked games and the tools that make them are usually shared as part of “warez,” an informal slang term for pirated software.

Most of this work happens inside an underground community known as “the Scene.” Within it, rival release groups race to be the first to publish a cracked copy of a new title. A release made on the same day as the original product, or even before it, is prized as a “0-day” release, and cracking a high-profile game on launch day is treated as a mark of skill. Many groups historically signed their work with a crack intro, or “cracktro”: a short animated screen, often with scrolling text and music, announcing who defeated the protection. Cracktro coding eventually grew into its own art form and helped seed the demoscene.

Tools Used In Cracking

Good tools are a critical part of successfully cracking software. There are many tools available online that let you see and manipulate the code of the game. Here are some of them:

Kernel-mode Debugger

Debuggers are software tools that enable a programmer to monitor the execution of a program. A kernel-mode lets the programmer run the debugger in the same PC that is being debugged. Kernel-mode debuggers help the programmer detect the lines of code where the user enters an invalid registration code and a message window informing them of this appears.

This information is crucial for the programmer to locate those lines of code and change them in such a way that disables or skips the built-in security.

Methods of Cracking

All the methods of cracking, in one way or another, are forms of reverse-engineering the game’s software. The process starts by examining the registry system and identifying ways to circumnavigate it. Usually, a patch is then provided so the user can run the identified loophole in their PC and bypass the registry system. Here are a few ways to do this:

Hex-Reading

This is the simplest of the available methods. This could be used in very simple games, as it is the entry-level of cracking. This works when a separate executable program is running the serial key registration. The process starts with examining where the registration takes place. For example, it could ask for the serial key, and upon entering the wrong one, it might display ‘Invalid Serial Key, Try again’. Now, a separate serial key registration file is run through a Hex-reader and the displayed term ‘Invalid Serial Key, Try again’ is searched. When the term is identified in the hex-reader, there is a string nearby that looks like a possible serial key. Entering that serial key should crack the game. Many companies have found workarounds to this method, so it works only on select games.

Hex-Editing

This process starts the same as before, by examining where the registration takes place. For example, let’s say the program asks for the serial key, and upon entering the wrong one, it displays ‘Registration failed’. This message should be noted or written down. As the simple approach to hex-reading doesn’t work here, the program is opened in the dissembler to understand the code of the game. The dissembler shows the code line by line. The strings used in the program show string references, which is how a person can find the message that was displayed (‘Registration failed’). This message box can be identified by clicking the reference that displays the code.  The code compares the entered serial key with a preset and jumps to start the program once it is finished.

This offset is noted and the file is opened again in a hex-editor; the code is changed to assembly, making it able to be edited. The offset is identified and the code is manipulated to jump, regardless of which serial key is inputted, thus cracking the game. This can also be done by changing the .dll or .so files linked to the game, which saves the expiration date and registry.

Finding and editing (Photo Credit : MicroOne/ Shutterstock)

Debugging

Sometimes the string reference is not hardcoded in the program, but may be accessed through other methods. In that case, the file is opened in a debugger like Syser to set a breakpoint in the program on a Windows API call (writefile, regcreatekeya, etc). The area of code is called and, similar to hex editing, a possible compare and jump instruction is located and edited so that it thinks the user has correctly entered the key when the patch is executed.

Keygen

This is the least invasive form of cracking. Say the program requires a 12-digit key of numbers from 0 to 9. The company makes their various keys as pattern-free as possible; so it becomes impossible to guess a serial number. However, when a user enters the serial key, the program knows whether or not the key is valid. The program checks a predetermined formula to verify the serial key, which is when dissembling comes in again. The programmer identifies what the program is coded to do when the serial key is inputted, takes the formula and writes another program that generates a serial key that fulfills the formula. This is usually done offline so the software doesn’t check the serial key with the parent website. The Keygen is then run by the user on their PC; the serial key matches the formula and is also patched.

How Are Modern Games With Denuvo Cracked?

The hex-editing and keygen tricks above belong to an earlier era, when a game’s protection was a single, easy-to-find serial-key check. Most big-budget PC titles today are wrapped in far tougher protection, the best known being Denuvo Anti-Tamper, made by the Austrian company Denuvo Software Solutions and first shipped with FIFA 15 in September 2014. Denuvo does not work by hiding one license check that you can jump over. Instead it ties a game to a unique authentication token generated from the player’s specific hardware, and it weaves thousands of encrypted checks deep into the game’s own code, so there is no single instruction to patch.

To defeat it, crackers reverse-engineer how Denuvo encrypts and verifies code at runtime, then rebuild a version of the executable that no longer needs those checks. This is painstaking work, which is why the very first Denuvo titles in late 2014 took the Chinese group 3DM around a month to crack. The protection has since weakened: by October 2017 some games were being bypassed within hours of release, and high-profile crackers such as CPY and EMPRESS became known for breaking it. From a publisher’s point of view, the goal was never to stay uncracked forever but to protect the crucial launch window. A 2024 study by William Volckmann in the journal Entertainment Computing, examining 86 Denuvo-protected Steam games, found that a quick crack cost publishers roughly 20% of total revenue on average, while piracy caused essentially no revenue loss when Denuvo held out for 12 weeks or more.

Denuvo is controversial with players, who blame it for stutters, longer load times, and reduced performance. The company denies that its software meaningfully degrades performance, but the friction is a big reason cracked, DRM-free copies remain in demand even when a game sells well legitimately.

Are Cracked Games Safe Or Legal?

On both counts, the honest answer is no. Distributing or downloading a cracked game means copying software without the copyright holder’s permission, which is copyright infringement in the United States, United Kingdom, Australia, Canada, and most other countries. That is the whole reason the “unwinnable war” between publishers and crackers exists in the first place.

The safety problem is more immediate. Because a cracked installer is an unsigned file from an anonymous source, it is an ideal way to smuggle in malware. The FBI, through the National Intellectual Property Rights Coordination Center, has warned that illegally copied software can carry hidden malware, and that once it is on your machine it can log your keystrokes to steal usernames and passwords, harvest personal information for identity theft, corrupt your data, or even switch on your webcam and microphone. Security researchers regularly trace password-stealing “infostealer” campaigns back to fake game cracks and repacked installers. In other words, the “free” game can cost you your accounts, your files, or your privacy.

Conclusion

This epic war between hackers and gaming companies is ongoing and seemingly here to stay. As programs get smarter and better encrypted, more advanced in their security, more sophisticated methods will be used to crack them. Perhaps companies will be able to make a completely hacker-proof game in the coming future, but as of today, there are plenty of workarounds that people will use to their advantage!