While working on an ERP project, a strange network traffic pattern I detected on a developer’s computer once again showed me how dangerous cracked software can be. When the user downloaded a “cracked” version of a design program, they actually infected their computer with an infostealer, which then began exfiltrating all passwords, cookies, and crypto wallet information from their browser. Infostealers are malicious software designed to silently infiltrate your computer and steal critical personal data; cracked programs are one of the most common vectors for distributing such threats.
These programs not only put individual users at risk but also pose serious security threats to the organizations they are connected to. An infostealer infecting a device of an employee who accesses corporate networks via VPN or RDP can easily bypass the company’s first line of defense. This situation demonstrates how an attempt to avoid a simple software cost can result in much larger data breaches and financial losses.
Why Are Cracked Programs So Dangerous?
Cracked software consists of unlicensed and often illegally obtained programs. While they may seem appealing to users looking for free software, the risks they carry far outweigh any perceived cost savings. Those who distribute these programs are often malicious actors who use these platforms to embed various types of malware onto users’ computers. In the examples I’ve seen, an infostealer hidden within a simple “crack” file can steal a user’s entire digital identity.
This situation is essentially a type of supply chain attack; by trusting a cracked version of software rather than the original supply chain, you expose yourself to malicious code inserted by intermediaries. Once this malicious code infiltrates your system, it doesn’t just steal your passwords; it can also enroll your computer into a botnet or infect it with ransomware. Users often dismiss antivirus software flagging crack files as “viruses,” assuming it’s a “false positive” and disabling the antivirus, thereby removing the last barrier against the malicious software.
What is an Infostealer and How Does It Work?
An infostealer, as its name suggests, is a type of malware designed to steal users’ personal information, credentials, and financial data. Such software typically operates in the background without the victim’s knowledge or consent, silently collecting data. In the incident we encountered in a production ERP environment, the infostealer collected a wide range of information, from passwords saved in the browser to crypto wallet keys.
The operating principle of an infostealer is usually simple, but its impact can be devastating. When the program is installed or executed, it scans specific locations on the computer for sensitive data. This data typically includes saved passwords from internet browsers (Chrome, Firefox, Edge, etc.), cookies, autofill data, cryptocurrency wallet files, screenshots, and even system information. It then encrypts this collected data and sends it to command and control (C2) servers.
graph TD; A["User Downloads/Executes"] --> B["Infostealer Activates"]; B --> C1["Browser Passwords/Cookies"]; B --> C2["Crypto Wallet Keys"]; B --> C3["System Info/Screenshots"]; C1 --> D["Data Collection"]; C2 --> D; C3 --> D; D --> E["Data Encryption"]; E --> F["Send to C2 Server"]; F --> G["Malicious Actor Accesses"];
Infostealers often have persistence mechanisms, meaning they automatically restart even if the computer is rebooted. This is usually achieved through autorun entries in the Windows registry, scheduled tasks, or files placed in startup folders. Once it infiltrates a system, it can be quite difficult to remove, sometimes requiring a complete reformat of the computer.
What Are Stolen Passwords Used For?
Passwords stolen by infostealers are golden for malicious actors and can be used for many different purposes. The most common use I’ve observed is for Account Takeover (ATO) attacks. An attacker who compromises a user’s email password can gain access to all other online services associated with that email address (banking, social media, e-commerce sites) and perform password reset operations.
In a corporate context, the situation is much more serious. If the stolen passwords include a company’s VPN or RDP access credentials, attackers can directly infiltrate the company’s internal network. This could mean direct access to sensitive systems like a bank’s internal platform, leading to severe data breaches. Furthermore, stolen credentials can be sold on the dark web, offering “initial access” to other cybercriminals.
Another use case is targeted attacks. Compromised cookies and browser history allow attackers to gain detailed information about the victim. This information can be used to craft more convincing phishing emails or social engineering attacks, coaxing the victim into revealing more sensitive information. For example, an attacker who knows a user shops at a particular e-commerce site could send a fake email in the name of that site to scam the user.
How Do I Know If I’m an Infostealer Victim?
It’s not always easy to tell if an infostealer has infected your computer, as these types of malware are often designed to operate stealthily. However, some signs can indicate the presence of a suspicious situation. First, you might start seeing unusual activities or login attempts on your accounts (email, social media, bank) that you didn’t initiate. For example, logins from an unrecognized location or un-sent emails could be indicators.
Second, you might observe unexpected performance drops or network activity on your computer. In a situation I experienced with the backend of my own side product, it wasn’t a slowdown from the servers, but network congestion caused by continuous data exfiltration from a user’s device that caught my attention. Checking current network connections and which programs are using them with the netstat -ano command is a good starting point for detecting suspicious activity.
netstat -ano | findstr ESTABLISHED | findstr /v "443"The command above, for Windows, shows active TCP connections other than port 443 (HTTPS) and can help identify suspicious, unencrypted (or encrypted on a different port) connections. On Linux, ss -tpna | grep ESTAB or lsof -i provide similar information. The appearance of unfamiliar new extensions in your browser or a change in your default search engine can also be a sign of an infostealer or other malware. However, these symptoms usually apply to simpler adware types; infostealers operate more stealthily.
How Do I Protect Myself and My Data?
The most fundamental step to protect against infostealers is to absolutely avoid cracked or unlicensed software. These programs often act as a Trojan horse for malicious software. Using licensed software is not only legal but also a critical security measure. Another important line of defense is to use strong, unique passwords and store them in a password manager.
For my part, I use different and complex passwords for each service; instead of memorizing them, I manage them with a password manager like Bitwarden. I also enable two-factor authentication (2FA or MFA) wherever possible. Even if an account password is stolen, 2FA prevents the attacker from accessing the account. This is an indispensable layer of security, especially for critical financial and email accounts.
Keeping your systems and software updated is also important. Operating systems and applications regularly release patches to close discovered security vulnerabilities. Neglecting these updates makes it easier for infostealers to exploit known weaknesses and infiltrate your system. Using a reliable antivirus or EDR (Endpoint Detection and Response) solution provides additional protection to detect and block malware. However, no software provides 100% protection; therefore, user behavior is also important.
How Do We Manage Infostealer Risk in a Corporate Environment?
Beyond individual users, corporate environments are also under threat from infostealers, and the measures to be taken here must be much more comprehensive. While developing an ERP for a manufacturing company, I saw how much importance the company placed on network segmentation; this is a critical step to limit the spread of internal threats like infostealers. Separating the company network with VLANs and applying specific access policies for each department or function prevents damage from spreading if a device is compromised.
Endpoint Detection and Response (EDR) systems are highly effective at catching infostealers by proactively monitoring and detecting suspicious behavior at endpoints. EDR solutions, with features like file integrity monitoring (FIM) and process monitoring, can identify changes made by infostealers in the system or attempts to exfiltrate data. Additionally, network monitoring solutions should be used to detect unusual connections or high-volume data exfiltration from the internal network to the outside.
User awareness training is also an important part of this fight. Regularly educating employees about the risks of cracked software, phishing attacks, and strong password policies reduces vulnerabilities stemming from the human factor. Finally, Privilege Access Management (PAM) solutions make it harder for infostealers to steal the credentials of administrators and other privileged users, preventing them from reaching their most valuable targets.
Conclusion
Downloading cracked programs, while initially seeming like an innocent and economical choice, can actually lead to paying a very high price for your digital security. Passwords stolen via infostealers can cause significant devastation in your personal and corporate life. To mitigate these risks, I always prefer to use licensed software, along with strong and unique passwords and two-factor authentication.
In corporate environments, individual measures alone are not enough; it’s essential to build a more layered defense mechanism by implementing network segmentation, EDR solutions, and Zero Trust principles. Remember, cybersecurity is like a chain, and it’s only as strong as its weakest link. Therefore, every user being aware and practicing basic security measures is vital to protect both our own data and the assets of the organizations we belong to.