In the world of cybersecurity, penetration testing is crucial for identifying vulnerabilities before malicious actors can exploit them. A significant aspect of these tests involves password security, particularly the ability to crack hashed passwords. Red teams, tasked with simulating real-world attacks, often rely on advanced tools and strategies to break these hashes. One such powerful combination is the use of Hashcat, a leading hash-cracking tool, with Hashtopolis, a distributed cracking platform that harnesses the power of GPUs across a team.
What Are Hashes and Why Do We Crack Them?
When a user creates a password, it’s not stored in plaintext. Instead, a hash function is used to generate a unique string of characters (the hash), which is stored securely. Hash functions are designed to be one-way, meaning you can’t reverse-engineer the input from the hash itself. This adds a layer of security, but it also means that to verify a password, the system must generate a hash of the entered password and compare it with the stored hash.
The challenge for attackers—and red teams—is to determine the original password that produced a given hash. This is done by generating potential hashes from a list of possible passwords and checking them against the target hash. The complexity of this task depends on both the strength of the password and the computational power available. Simple passwords can be cracked relatively quickly, while more complex passwords can require immense processing power to break.
Enter Hashcat: The Go-To Tool for Hash Cracking
Hashcat is a versatile and widely-used tool in penetration testing. It supports over 350 hash algorithms and can be configured to use different attack modes, such as dictionary attacks, brute-force, and combinator attacks. One of Hashcat's most powerful features is its ability to leverage GPUs (Graphics Processing Units) for hash cracking.
GPUs are particularly suited for this task because they contain thousands of cores that can handle multiple hash computations in parallel. This makes them exponentially faster than CPUs for specific types of calculations, such as those required for cracking passwords.
Scaling Up with Hashtopolis
While a single GPU can significantly speed up the hash-cracking process, large-scale penetration tests often require even more power. This is where Hashtopolis comes into play. Hashtopolis is a wrapper for Hashcat that enables distributed hash cracking across multiple machines and GPUs. By pooling together the resources of a red team, Hashtopolis allows for a much larger and faster attack surface.
How Does Hashtopolis Work?
Hashtopolis operates using a client-server architecture. The server is responsible for managing the overall task of hash cracking, including distributing workloads, monitoring progress, and gathering results. The agents (clients) are the machines that do the actual cracking, each equipped with their own GPUs.
Server Setup: The Hashtopolis server can be easily deployed using Docker. It’s the central hub that coordinates the distributed cracking effort, storing hash lists, wordlists, and managing tasks.
Client Deployment: Agents are lightweight Python applications that can be installed on almost any computer. These agents communicate with the server via an API, reporting their available resources and requesting tasks.
Task Distribution: When an agent is assigned a task, it downloads the necessary hash lists, wordlists, and Hashcat binaries from the server. It then uses its GPUs to crack the hashes and reports back its progress and results in real-time.
Monitoring and Management: The Hashtopolis web interface provides real-time monitoring of each agent's performance, allowing red team operators to manage resources effectively and identify potential bottlenecks.
The Power of Collaboration in Red Team Operations
By distributing the workload across multiple machines, Hashtopolis enables a red team to crack hashes much faster than any single system could. This is especially valuable in time-sensitive penetration tests, where the ability to quickly break into a system can be crucial for identifying vulnerabilities.
Moreover, this collaborative approach allows teams to make use of all available hardware, maximizing the efficiency of the operation. It also helps in handling more extensive hash lists or more complex passwords that would be nearly impossible to crack with limited resources.
Why Does This Matter?
During penetration tests, especially those conducted by Exploit Labs, cracking hashes is a practical way to demonstrate the security—or lack thereof—of a client’s password policies. If a red team can break a password within hours, it highlights a critical vulnerability that needs addressing.
Leveraging tools like Hashcat and Hashtopolis, red teams can significantly enhance their ability to crack hashes, providing more comprehensive security assessments for their clients. By utilizing the combined power of multiple GPUs across different machines, teams can tackle even the most complex password hashes, ensuring that no stone is left unturned in the quest for security.
In the ever-evolving field of cybersecurity, staying ahead of potential threats means adopting and optimizing the latest tools and techniques. For red teams, Hashtopolis offers a powerful solution for distributed hash cracking, transforming a challenging task into a more manageable and efficient process.
Finally, it's a great incentive to equip your team with powerful GPUs, encouraging them to collaborate when someone calls for assistance. It's far better to harness the combined power of all team members and their GPUs remotely than to be stuck alone in a hotel room, relying on your laptop's GPU, which ends up heating the room while you sleep.