The Unexpected Challenge at a Premier Hacker Gathering

In November 2017, the vibrant city of Moscow hosted a unique congregation of cybersecurity enthusiasts, an event that felt more like a family reunion for the Russian information security community than a typical conference. Dubbed “Zero Nights,” this gathering echoed the spirit of renowned events like DEF CON, blending cutting-edge research with thrilling, hands-on challenges. For me, a seasoned security specialist with roots in competitive CTF (Capture The Flag) hacking, it was a return to a playground where intellect and ingenuity reigned supreme. Little did I know, this conference would lead me to a challenge far removed from my usual digital exploits: cracking an analog safe using nothing but patience and acute observation.

Zero Nights: A Hub of Innovation and Community

Zero Nights distinguished itself from corporate security summits by fostering a strong sense of community and prioritizing hands-on experience. The 2017 edition continued this tradition, featuring:

• Insightful Discussions: Covering everything from critical infrastructure vulnerabilities to advanced web exploitation.
• Interactive Hacking Villages: Where attendees could test their skills against diverse systems.
• Hardware Hacking Zone: A playground for those eager to disassemble and understand physical devices.
• The Enigmatic Safe-Cracking Challenge: A vintage Soviet-era safe, its dial silently daring participants to unlock its secrets without force.

This emphasis on practical application and collaborative spirit truly embodied the hacker ethos: understanding systems by breaking them, not for malice, but to build stronger defenses.

The Analog Enigma: No Digital Shortcuts Here

The safe-cracking challenge was deceptively simple: “Open the analog safe without force.” The rules were strict and clear, prohibiting any physical damage or destructive methods. Teams of up to five could participate, vying for glory and prizes. For a crowd accustomed to binary exploitation, web application attacks, and the digital realm’s complexities, this mechanical puzzle presented an entirely different kind of intellectual battle. Our usual arsenal of scripts, debuggers, and exploit code was rendered useless. This was pure, back-to-basics security research, demanding an intimate understanding of a physical system through analysis.

Assembling the Team and Learning to Listen

Though I initially attended as a journalist, the allure of the challenge was irresistible. I quickly joined a diverse team of digital specialists, united by curiosity. Our initial approaches, predictably, reflected our digital mindsets: “Could we use a side-channel attack on the dial?” or “What about acoustic analysis of the clicks?” We even tried a smartphone stethoscope app! After several amusing failures, we realized we needed to pivot, to truly understand the fundamental mechanics of how safes operate.

Mechanical combination safes typically employ a “wheel pack” system. A spindle, connected to the dial, runs through several wheels, each with a precisely cut notch, or “gate.” The combination aligns these gates, allowing a metal lever (the “fence”) to drop into them, which in turn permits the bolt to retract and the safe to open. Our task was to discern these alignments without knowing the combination.

The breakthrough came when we shifted our focus from digital analysis to acute sensory perception. We began to “listen” to the safe, not just with our ears, but with our fingertips. We discovered subtle auditory and tactile feedback points as the dial turned. Key insights emerged:

• The third number in a combination often presented the least resistance when correctly aligned.
• A barely perceptible “click” could be felt more than heard, signaling critical points.
• Slight variations in dial tension at specific positions offered crucial clues.

Our team divided responsibilities: one member with sensitive hands focused on tactile feedback, another with a keen ear listened for auditory cues, a third meticulously tracked dial positions, while I coordinated our efforts and documented our painstaking process.

The Methodical Hunt for the Combination

After hours of meticulous testing and observation, punctuated by strategic coffee breaks, we began to map out potential numbers for each part of the combination. The real genius emerged as we understood that the mechanism required specific sequencing, much like the precision of timing attacks in cryptography.

Our approach involved:

1. Identifying “Sticking Points”: By slowly turning the dial counter-clockwise after multiple clockwise rotations (to reset the wheels), we’d feel subtle “clicks” or points of increased resistance. These indicated where the drive pin contacted a wheel. The strongest or loudest of these often corresponded to the last number.
2. Pinpointing the First Number: This was the most time-consuming phase. We’d systematically test each number. For each, we’d apply slight pressure and slowly turn the dial clockwise, feeling for a “false gate” – a momentary increase in resistance, followed by ease. The number with the widest or most pronounced false gate was often the first number of the combination.
3. Brute-Forcing the Middle Number: With the first and last numbers tentatively identified, finding the middle number became a process of careful triangulation. After resetting and setting the first number, we’d turn the dial slowly towards the last number, keenly feeling for a “hiccup,” a brief slip or looseness, indicating when the fence dropped into the middle wheel’s gate.

The Sweet Sound of Success

The moment of truth arrived on the second day of the conference, at precisely 4:37 PM. After countless iterations and fine-tuning based on our collective observations, Dmitry, our tactile expert, slowly rotated the dial through what we believed was the correct sequence: 17-33-49.

A deeply satisfying “clunk” resonated through the quiet hall – music to our ears. The handle turned smoothly, and the heavy door swung open to reveal… conference swag. But the contents were secondary. We hadn’t overpowered the mechanical beast; we had outsmarted it. The gathering crowd erupted in cheers; in the hacker community, every successful solve is a shared triumph.

Lessons That Transcended the Physical

This challenge offered invaluable insights that directly apply to the digital security landscape:

1. Physicality Matters: Even in our cloud-centric world, systems have physical elements that can be exploited – a critical oversight for many.
2. Patience vs. Brute Force: Meticulous observation and strategic patience often yield greater results than aggressive, resource-intensive brute force, whether in analog or digital domains.
3. Interdisciplinary Power: Diverse perspectives, brought by teams with varied skill sets, are crucial for cracking complex problems.
4. Know Your Adversary: Understanding the fundamental construction and operation of any system is the prerequisite for identifying and exploiting its vulnerabilities.

The safe challenge perfectly encapsulated the true hacker spirit: a drive not to destroy, but to understand. Just as in CTF competitions, the objective was mastery through comprehension – breaking something down to ultimately build it better.

Keeping the Hacker Spirit Alive

Reflecting on Zero Nights 2017, I’m filled with nostalgia for that unparalleled community atmosphere. The analog safe challenge was far more than a mere diversion; it was a living embodiment of hacker culture at its finest:

• Curiosity-Driven Exploration: A pursuit of knowledge without malicious intent.
• Collaborative Problem-Solving: Transcending competitive instincts for shared success.
• Respect for Systems: A desire to understand their inner workings, even while finding ways to bypass them.
• Pure Joy of Learning: The profound satisfaction derived from hands-on discovery.

In an increasingly virtual world, physical challenges that bring people together in shared space and time offer a unique and profound experience. The emotional high of that safe-cracking victory remains far more vivid than many digital penetration test findings.

So, here’s to the hackers, the breakers, and the perpetually curious minds who dissect and delve into systems to uncover their secrets. May our culture of creative exploration forever thrive! Whether it’s exploiting a binary, discovering a web vulnerability, or cracking an analog safe, the core principle endures: “It’s there, let’s see how it works!”