Learn the rules: The hacker mindset
Microsoft Research manager Mike Walker traces a career from childhood tinkering and bulletin board systems through DEF CON Capture the Flag, DARPA’s Cyber Grand Challenge, and today’s AI-driven cyber defense. He explores why rules are social constructs built on trust, how offense and defense are dual-use, why tampering is often the easiest attack path, and why teams need social intelligence as much as technical skill.
Rules, in Mike Walker’s view, are a social construct, and every time a security system asks something of its users, it is asking for their trust. “When you squander user trust, then the security regime falls down.” Understanding the social context of a rule matters more than instantly deciding whether it was broken. That idea runs through a career that started with a childhood of taking things apart and led to DARPA’s autonomous hacking program and Microsoft Research.
Growing up with tools and no one to talk to
Walker grew up in Columbus, Ohio, and spent summers on a farm in Tappahannock, Virginia, on the Rappahannock River. His father, half scientist and half venture capitalist, brought home industrial equipment and left him to work out what he could build from it, including a helium neon laser with a high-voltage supply and the mirrors and table needed to try replicating the Michelson-Morley experiment. The Apple II was another obsession, a machine that seemed to come from another universe, and he tried to wire it into the rest of his life. He later recognized this as hacker culture, but at the time there was no one to talk to about it. He ran a bulletin board system, each one a small universe built by its operator. All of this turned into a career once the world began hiring people to impose rules on networked computers. “I was always here, but now it has a name.”
Rules, judgment, and a game about adjudication
Walker is fascinated by rules, but he insists you must understand why they exist before you can work within them. He describes the game No Vehicles in the Park as a thought experiment about content moderation. Players act as judges on questions like whether the International Space Station flying over the park violates the rule, and the exercise shows that even simple rules need a resilient way to bridge social norms. He has rarely scored above 50 percent, and a high agreement with the crowd means you “channel the zeitgeist.”
Entering the Capture the Flag world
After September 11, 2001, while working at a telecommunications startup in Maryland with his wife in Washington, D.C., he was found by a talent search for people who understood computer security, or who had always been doing that work without knowing what it was called. What followed was roughly eleven years of getting better at hacking, and the DEF CON Capture the Flag scene was the crucible. In a coffeehouse-style environment where everyone is trying to improve, competing at a national or international level propels you upward quickly. The game has changed with each generation. Eight to sixteen teams try to take each other’s flags while protecting their own. Flags are data or control of a networked system, and the software is boutique: written by organizers, kept secret, revealed the moment teams sit down, and never used again. Whoever understands it fastest can both protect it and hack it.
From human hackers to machine hackers
RAND had published “Hackers Wanted,” describing the urgent need for people who could think this way at a high level. At DARPA, Norm Whitaker and Dan Kaufman, leading the Information Innovation Office, asked a question that framed everything that followed: if Capture the Flag is human soccer, what about robot soccer? Could machines play? That question led to the Cyber Grand Challenge (CGC), the world’s first all-machine hacking tournament. Walker served as a program manager at DARPA for about four years, and the effort took three and a half years to come together. Teams had built autonomous systems, but a system designed to fight cannot be preflighted the way one can be taken for a drive. DARPA’s infrastructure team built a scripted opponent to offer some pre-exposure, yet the first confrontation between adversarial hacking machines had little real preparation. Everything ran behind an air gap, so if a system failed, no person was there to restart it.
Expert systems, models, and the change in capability
CGC was an expert-systems contest, and machine learning played no critical role at the time. Still, it helped shape the technology stacks that followed. Walker stresses how radically different today’s model intelligence is from what existed in 2013 to 2016, and yet the tooling from that era persists as what is now called a harness. Team Atlanta, which won DARPA’s AI Cyber Challenge (AIxCC), is building MDASH, a cyber reasoning system powered by models that performs these tasks autonomously.
In 2016 he described making networked technology safer as a challenge for civilization, and he thinks that is as true now, perhaps more so. Civilization’s dependence on networked systems has only grown; it is hard to buy a car or join a utility grid that is not networked. He argues that security had settled into a steady-state equilibrium anchored by offensive scarcity, a known cost for high-end network attack. Models have upended that cost equation, and the consequences are still unfolding.
Red, blue, and purple
Red and blue teams create an artificial separation between attackers and defenders, and it oversimplifies what happens under the hood. The difference between offense and defense is most often who holds the key. An encryption utility that locks and unlocks your files is cryptography or ransomware depending on who controls it. Remote access software is either malware or a legitimate remote administration tool depending on who controls it. Computer security capabilities are dual use at their most atomic level. Attackers defend their intrusions, avoid detection, and move laterally while they work. Defenders must protect their own tooling, find vulnerabilities, and prove them with exploits, which is offensive work. Purple teaming acknowledges that attack and defense share the same skill set and tooling, and that the real contest is over control of the logic and memory of networked machines that run all the time.
Walker’s team, New Security Ventures, does what he calls highly offense-aware defensive tool development: they build defensive tools with the understanding that those tools will be targeted.
Project Freta and the problem of tampering
Project Freta is named after the birthplace of Marie Curie, the pioneer of battlefield imaging. Walker explains tampering with a store analogy. Breaking in and walking out with merchandise unseen is hard, but it is often easier to wave at the camera, cut the feed, and substitute a fake video of an empty store. In computer security, tampering is frequently the easiest path to an attacker’s objective, and attackers do defense while they do offense. Freta addresses this at cloud scale: defenders gather telemetry from cloud hardware rather than from software that can be removed or altered. It is a whole-system memory analysis environment built from the ground up for memory acquired from cloud hardware.
Revealing how a system works is different from revealing how it is deployed. Attackers adjust their behavior based on what they believe defenders are doing, which makes the question of whether to claim a capability, possess it, or create a deliberate mismatch between the two a strategic one. Walker notes that this is why the game is played in Vegas.
Endurance, injury, and a gravel bike built one-handed
Cycling entered his life through an injury. After a blown-out knee from basketball, a surgeon suggested swimming or biking, and a college friend introduced him to mountain biking, which turns a stable machine into something for steep, rough terrain. Preparing for the High Cascades 100 meant structured indoor training starting around January for a July race. He was advised not to become a “trainer robot,” and learned to ease off erg mode and listen to his body on free-ride terrain. For him, the suffering is in the logistics and the worry before the start, such as chasing a flat tire fix the day before the race. Once racing begins, it is the best part. He finished 69th out of 329 participants. His project bike, Orange Crush, was built during a shoulder injury, mostly left-handed, and his wife named it. He races, he says, to learn about himself, and he takes on hard technical problems partly because solving them is what he has always done and partly because of the people and the impact.
Leadership, humility, and social intelligence
A mentor once asked him whether the decisions he disagreed with might stem from information he did not have. When he was shown the missing context, a decision he had criticized looked excellent, and that experience reshaped how he thinks about leadership. Now he asks, every time, “What do they know that I don’t?”
His most humbling moment came in a hacking qualifier, when he ran up with a key for a challenge that his team had solved an hour and a half earlier. Looking around the room, he realized he could quantify the intelligence of the people there but could not measure how well they worked together, whether they were aligned, or whether they were on the right challenges. That led him to think about social intelligence in technical teams and to move away from the hero journey. Organizations that do not invest in their EQ, he argues, end up with people chasing keys to problems already solved.
Beyond security
If he had not pursued cybersecurity, he would have been a science fiction writer, and he wishes he had stuck with it longer. He recommends Joe Haldeman’s The Forever War, which he describes as a story about arriving with the key only to find the challenge already solved, in a universe governed by relativity. He also taught himself to juggle while recovering from knee surgery, confined to a space small enough that the balls could not get away from him, a skill he still has.