Physical security is often an overlooked area of cybersecurity. If the attacker can physically gain access to your facility and your devices, GAME OVER! As a result, we have begun a new tutorial series and classes on physical security.
Introduction
Lock picking is a critical skill in a pentester’s toolkit, allowing them to bypass physical security measures non-destructively. One of the most precise and effective methods of lock picking is Single Pin Picking (SPP), where each pin inside the lock is manipulated individually. While basic SPP can be mastered quickly, advanced techniques require a deep understanding of lock mechanisms, precision, and a mastery of tactile feedback.
This guide explores advanced single-pin picking techniques for pentesters, focusing on detailed methods to overcome sophisticated lock systems in various real-world environments. Mastery of these techniques will not only help you gain access to restricted areas more effectively but will also strengthen your understanding of lock vulnerabilities, aiding in comprehensive physical security assessments.
Let’s do a quick review of lock-picking essentials
Finding the binding pins and using single pin picking to set them in the correct order
Binding Pin Recognition
The binding pin is the first pin that resists movement when tension is applied. Advanced locks often have security pins that bind irregularly. Identifying which pin is binding first and applying the right amount of upward pressure is the key to making progress. Use a systematic approach, probing each pin gently and identifying the one that feels solid or slightly stuck.Tolerances in the plug holes cause pins to bind in a random order.Front view of setting the first binding pin past the shear lineCommon error, oversetting a key pin past the shear line and releasing too much tension, which resets the lock
Advanced Techniques for Single Pin Picking
Mastery of advanced SPP relies heavily on refining your tactile sensitivity, understanding pin feedback, and manipulating difficult lock mechanisms with precision. Below are advanced techniques designed to overcome the challenges presented by security pins and complex locking systems.
The Importance of Tension Control
Tension is the foundation of successful lock picking. Without proper tension control, even the most experienced picker will fail to open complex locks. High-security locks often require extremely light tension to pick. These locks are designed to have tight tolerances and bind pins very easily. Applying too much tension may cause pins to set too tightly or bind in a way that provides no useful feedback. Mastering light tension involves balancing just enough pressure to keep the driver pins from dropping back down, while still allowing the pins to move freely.
Varying Tension
Complex locks with security pins often require variable tension techniques. After setting one or more pins, you may need to increase or decrease tension to manipulate subsequent pins without resetting the lock. This ability to “feel” the lock as you adjust tension dynamically is key to opening high-security systems.
- Start with light tension to explore how the pins respond.
- Increase tension slightly as some pins begin to bind, giving more control over individual pin movements.
- Decrease tension occasionally if pins are over-set or to allow movement of stubborn pins.
The Jiggle Test
The jiggle test is a technique used in lockpicking to determine whether a pin has been properly set or over-set within the lock. It’s a simple but effective way to gain feedback on the state of each pin as you manipulate them. This test involves gently applying a “jiggling” motion to the lockpick, allowing you to feel if a pin is loose, set correctly, or stuck.
How the Jiggle Test Works:
After applying tension, insert your lockpick into the keyway and begin manipulating the pins as you normally would, pressing each pin upwards to try to set it into the shear line. Once you believe a pin is set (or you’ve made progress with several pins), gently test each row of pins by jiggling the lockpick up and down while keeping light tension on the wrench. This subtle movement helps to test the state of each pin. Here’s what you might feel:
- Unset Pins: The pin goes up and down freely with consistent downward force from the spring. This means the pin hasn’t reached the shear line and isn’t set. This also means that this pin is not the current binding pin.
- Under-Set Pins: If a pin moves freely with the initial touch, but as you progress the pick upward the pin feels tight and doesn’t move then you may have an under-set pin. Release some tension and continue to apply upward pressure until you feel a click.
- Set Pins: When you initially lift the key pin will have no downward force from the spring, it will feel jiggly. As you continue to lift the key pin you encounter the driver pin at the shear line, which will move freely but you feel the downward force of the spring. As you slowly lower the pick you will also feel the driver pin catch on the shear line and the downward force of the spring will not follow as you lower the key pin. This pin doesn’t need further manipulation, and you can move on to the next one.
- Over-Set Pins: You initially feel a void where the key pin should be resting. As you raise the pick and touch the pin it will feel overly tight and won’t move at all. This means the pin is over-set, lightly release tension and allow the key pin to drop.
Based on the feedback from the jiggle test, you can adjust your approach. If a pin feels loose, keep working on it. If it feels tight but the lock isn’t opening, consider the possibility of an over-set pin and release some tension to reset the problematic pin.
Pin Identification and Feedback
In advanced SPP, the ability to identify and react to the feedback provided by each pin becomes critical. Pin stacks behave differently depending on whether the pin is a standard or security pin. Single pin picking mastery requires practice until you learn to interpret the tactile feedback from how the pin moves and how the tension wrench reacts.
Differentiating Standard Pins from Security Pins
Security pins give different feedback compared to standard pins. When a standard pin is lifted, it will feel smooth, and the tension wrench will rotate slightly with the pin’s movement. However, with security pins, the feedback can be deceptive.
- Spool Pins: These have a narrowing in the middle, creating a false set where the plug rotates slightly, but the lock does not open.
- Serrated Pins: These pins will give multiple clicks as you lift them, often making it difficult to tell when they are properly set.
- Mushroom Pins: This pin gets its name from its shape, which resembles a mushroom with a tapering stem and a wide cap.
Feedback through the Tension Wrench
The tension wrench is more than just a tool to apply rotational force; it serves as your primary conduit for feedback from the lock’s plug. This indirect feedback is crucial for interpreting the behavior of individual pins in complex, high-security locks with security pins. Advanced pickers learn to read these subtle movements and use them to make informed decisions about how to proceed with picking.
As you apply rotational force with the tension wrench, the plug will resist movement until one or more pins are set. The moment a pin sets, the plug may move very slightly—often imperceptibly to the eye, but detectable through the tension wrench. This shift in the plug, however small, provides valuable feedback about the state of the lock.
For example, when a standard pin is set, the plug may “click” into place with a small but noticeable rotation. This gives the picker confirmation that the pin has reached its shear line. However, when security pins are involved, the feedback becomes more nuanced. Spool and mushroom pins, for instance, give the illusion that they are set, but subtle movements in the plug will indicate a false set and a pending need for counter-rotation.
Techniques for Manipulating Security Pins
Security pins are designed to resist picking by creating false feedback. They are typically found in higher-grade locks and, without the proper understanding, are a significant barrier for novice pickers. The following techniques help in overcoming these challenges.
Counter-Rotation for Spool Pins
Spool pins are among the most common security pins and are designed to produce false sets. When you apply tension, the spool pin will bind, and the plug will rotate slightly (indicating a false set). To identify the false set spool pin, you must release some tension from the tension wrench. Then use a hook pick to perform the jiggle test until you find the pin that causes the plug to counter-rotate (closely watch the black tick lines on the gif below to illustrate counter-rotation). Lightly let up on the tension wrench and push the spool pin until it sets. This process is delicate—releasing too much tension will reset the lock, while too little tension will not allow the counter-rotation.
Serrated Pin Manipulation
While spool pins use plug rotation to confuse you, serrated pins mimic the feeling of a set pin with “clicks”. Instead of pin sets, these clicks are the pin catching on one of its serrations on the shear line. The key to mastering serrated pin is learning to distinguish the lighter and more dull feeling clicks of the serrations compared to a set click. When you find an under-set serrated pin, apply very light tension to the wrench and slowly lift the pin, feeling each serration click into place.
Manipulating Mushroom Pins
Mushroom pins are functionally spool pins but these pins are trickier. Due to their tapered stem they allow the plug to rotate further, thereby more closely mimicking the feel of a properly set pin than a spool pin. That being said, the process of setting mushroom pins is very similar to spool picking. The primary difference is that, due to the tapered stem, a mushroom pin only starts to counter-rotate when you have almost set it. (In comparison, the spool pin will almost immediately start to counter-rotate when you apply force.) With this in mind, understand you only need to lift the mushroom pin slightly when it begins to counter-rotate, or you risk oversetting it.
Lock picking, while a valuable skill for pentesters, also comes with ethical and legal responsibilities. Always ensure that you have proper authorization before picking any locks. Unauthorized lock picking can be illegal in many jurisdictions and could lead to legal consequences, even if done in the name of security testing.
Always operate within the guidelines of your contract, and make sure the client understands the scope of your physical security testing, including any lock-picking activities.
Conclusion
Advanced single pin picking is a crucial skill for pentesters looking to improve their ability to bypass physical security systems. By mastering tension control, pin feedback interpretation, and handling high-security locks, you can increase your efficiency and success in the field. Continuous practice on a variety of locks, under different environmental conditions, will enhance your skills and prepare you for real-world pentesting challenges.
During a recent bank audit, your SPP techniques helped bypass a “secure” cabinet holding network keys. This post proves physical security is often the weakest link. Include case studies showing how SPP prevented costly breaches. Advice: Pair SPP with RFID cloning tools for comprehensive testing. Ethical hackers NEED this to stay ahead
Your SPP guide transformed my approach to physical engagements. By understanding lock mechanics, I’ve identified vulnerabilities in office complexes that digital tools alone couldn’t expose. For hackers, this skill builds patience and precision. I’d suggest adding a section on common lock brands to avoid (e.g., Master Lock No. 3) and recommending high-quality picks like Sparrows. This knowledge isn’t just offensive it’s crucial for designing tamper-proof spaces
I applaud your clear explanation of binding order and feedback. Teaching SPP helps students grasp physical security’s human element like social engineering via lock flaws. Include advice on progressive locks for practice: start with 2 pins, advance to 6. Also, warn about legal boundaries; I require certification (e.g., OSIP) for students. This post is a must-read for anyone in security certifications.
SPP skills improved my IoT work e.g., hacking smart locks via physical bypass. Add a section on electronic lock weaknesses (power jamming). I combine SPP with lock decoding for non-destructive entry. This post is a blueprint for hybrid threat analysis!
As a beginner, your step-by-step tension control guide helped me avoid frustration. Start with Kwikset locks—their wide tolerances forgive errors. Suggest timing drills: aim for <60 seconds per lock. This post made me realize physical security isn’t about impenetrability but slowing attackers. Inspiring!
In an AI-dominated world, your post reminds us that analog threats persist. I teach SPP to illustrate attack evolution—from skeleton keys to bumping. Advocate for biometric + mechanical hybrid systems. This knowledge isn’t obsolete; it’s foundational. Bravo for keeping physical security relevant.
Your emphasis on legality (e.g., “no picking locks you rely on!”) is vital. I use SPP only in labs or authorized engagements. Suggest joining locksport groups (TOOL) for community practice. This skill boosted my consulting credibility clients value actionable fixes like installing Mul-T-Lock cylinders. A responsible, enlightening read!
Securing our industrial control systems (OT) was daunting. Finding ethical hackers with genuine OT/IoT expertise was challenging until we found you. Your team understood the unique protocols, physical constraints, and criticality of our operational environment. They safely identified vulnerabilities in PLCs and network segmentation without disrupting operations. The specialized recommendations significantly hardened our previously exposed OT infrastructure against potentially catastrophic attacks.
the most valuable part wasn’t just the findings list, but the collaborative remediation workshops your team offered for our developers. Walking through the how and why of the vulnerabilities they exploited, providing secure coding examples, and answering specific questions dramatically improved our developers’ security mindset and coding practices. This knowledge transfer builds lasting internal capability, making future applications more secure by design.
This isn’t just lockpicking it’s a masterclass in threat modeling. Your post showed how SPP exposes design flaws (e.g., poor tolerances) in budget locks. For homeowners, this knowledge justifies upgrading to high-security locks like Medeco. Pentesters should document these weaknesses in reports to push clients toward solutions. Add a tip about using a plug spinner for accidental reversals.
our point about SPP requiring calm focus is spot-on. This skill trains hackers to handle high-pressure infiltrations. Recommend meditation alongside practice. Also, discuss social engineering synergies—e.g., picking during distractions. Uniquely valuable.
This post brilliantly demystifies single-pin picking (SPP) for security professionals. As a pentester, mastering SPP has been invaluable during physical security audits—it reveals how easily low-security locks can compromise entire systems. I recommend pairing this with a transparent practice lock to visualize pin states. Also, emphasize ethics: always obtain written consent before testing. Your breakdown of tension wrench techniques alone helped me reduce bypass time by 40%!
Brilliant how you link SPP to broader risks e.g., a picked file cabinet can reveal network diagrams. Pentesters should integrate this with Wi-Fi hacking (rogue APs near entry points). Tip: Use a decoy lock during engagements to avoid suspicion. Your post turns a niche skill into systemic risk awareness!
While you helped us meet specific compliance requirements (PCI DSS, SOC 2), your service delivered far more than just a checkbox. You focused on finding real security risks that could actually be exploited, not just theoretical or compliance-specific items. This commitment to genuine security posture improvement, going beyond the bare minimum, is what sets true professional ethical hackers apart. You made us genuinely more secure, not just compliant.
your post saved my firm $10k! We found SPP vulnerabilities in server-room locks and upgraded to ASSA Abloy for under $500. Recommend clients use Burg Wachter for budget solutions. Pentesters: quantify this risk in reports—e.g., “60-second bypass = critical flaw.” Pragmatic genius!
Your SPP tutorial refined my dexterity and analytical thinking critical for cybersecurity pros who overlook physical vectors. I spent weeks practicing with a cutaway lock, and now I can assess lock resilience in minutes. Recommend Peterson’s “Government Steel” picks for durability. Also, discuss raking vs. SPP: when speed matters versus stealth. This post bridges the gap between hackers and locksmiths.
Learning SPP landed me a physical pentesting role! Your breakdown of security pins (serrated vs. mushroom) helped me tackle advanced locks. Add resources: “Lockpicking: Detail Overkill” PDF or Lock Noob’s YouTube series. For pros, recommend creating a “lock library” to catalog vulnerabilities. This post is a career catalyst!
Love your focus on minimal tools (hook pick + wrench)! Beginners often overbuy kits. I’d add a comparison table: SouthOrd vs. Multipick for feedback sensitivity. Also, recommend lubricants (Tri-Flow) for sticky locks. This post taught me that 90% of locks fail against SPP now I advise clients on anti-pick pins like spools. Practical and eye-opening!
During a critical acquisition, understanding the target company’s real security posture was paramount. Your discreet, thorough ethical hacking assessment of their systems revealed significant undisclosed vulnerabilities and lax security practices. This critical intelligence allowed us to renegotiate terms, factor in remediation costs, and avoid inheriting massive hidden risks. Your work was indispensable for informed decision-making and protecting our investment.
As a cyber specialist, I underestimated physical attacks until your post. SPP taught me persistence each pin set is like cracking a password character. Recommend combining it with covert entry (e.g., shimming) for layered assessments. Stress the importance of gutting locks post-practice to study mechanics. This knowledge is empowering and humbling
I now include lockpicking in vulnerability assessments after reading this. SPP reveals supply chain issues (e.g., reused keys). Recommend the “Covert Instruments” practice sets. Highlight forensic signs of picking to help clients detect intrusions. Transformative for security hardening.
Your secure code review significantly improved our SDLC. Providing developers with specific, contextual feedback on vulnerabilities in their code was far more effective than generic training. A fantastic way to build security in from the start.