BREAKING

Profile / Founder + CTO

Yonatan
Striem-Amit

The kid who broke video games. The soldier who broke into networks. The founder who's building AI to break the attacker's speed advantage - for good.

He reverse-engineered a game at age 12 to give himself infinite coins. At 18, Israel's elite intelligence corps recruited him before he'd written a single line of academic code. At 40-something, he closed the largest Series A in cybersecurity history. The thread connecting all three moments is the same: he keeps finding the seam where the system bends.

7AI Co-Founder Unit 8200 Veteran Cybereason CTO $166M+ Raised Agentic Security
Yonatan Striem-Amit

The Origin

Coins That Multiplied on Purchase

Around the age of twelve, Yonatan Striem-Amit sat down with a video game he wanted to play more of, but couldn't afford more coins to play it with. So he did what turned out to be a defining thing: he opened the binary, found the routine that decremented his balance, and inverted it. From that point on, buying items made him richer.

It wasn't that he was clever - most kids with enough obsession and time figure out a version of this trick. What was different was that he kept going. He kept pulling threads in systems, kept looking for the model behind the behavior, kept asking what happens when I press here? He taught himself systems programming before systems programming was a career path most teenagers knew about.

When the Israel Defense Forces came looking for recruits for Unit 8200 - the signals intelligence division that functions roughly as Israel's NSA, staffed not by credential-holders but by teenagers who had already proven they could navigate complexity - Yonatan was 18, and he had never taken a formal computer science class. He had, however, spent years taking software apart.

They took him anyway. The IDF usually did, for kids like that.

Unit 8200 is where careers in Israeli cybersecurity are forged. The alumni list reads like a who's-who of the global security industry - founders of Check Point, Palo Alto Networks, SentinelOne, and dozens of smaller companies that quietly handle the world's most sensitive networks. Yonatan spent four years there learning how offense actually works - not from textbooks, but from doing it, and watching it be done to others.

He came out the other side understanding something that most defenders never quite grasp: the attacker is always ahead, not because they're smarter, but because they only have to find one gap. Defenders have to cover everything. The asymmetry isn't a technology problem. It's a time-and-attention problem.

That insight would take another twenty years to fully pay off. But it was always the thing he was building toward.

At a Glance
Current Role Co-Founder & CTO
7AI
Prior Cybereason CTO
Education MSc CS / ML
Hebrew University
Intelligence IDF Unit 8200
Location McLean, VA
Citations 784+
Attackers share exploits and test new methods within their communities almost overnight. Traditional security teams still require years to adapt. That gap is the whole problem.

- Yonatan Striem-Amit

$130M Series A - Largest in Cybersecurity History
$166M+ Total Raised at 7AI
784+ Academic Citations
25+ Years in Cybersecurity
2 Co-Founded with Same Partner

Act Two

How Three People Built an EDR Company Worth Hundreds of Millions

In 2012, Yonatan Striem-Amit sat down with Lior Div and Yossi Naar - two other Unit 8200 veterans - and started Cybereason out of Boston. The timing was either very good or very bad, depending on how you looked at it. The security industry was dominated by perimeter defenses: firewalls, antivirus, the idea that you kept the bad guys out. The problem was the bad guys had already figured out that getting in was easy. What they hadn't figured out yet was what to do after they got in.

That's the space Cybereason occupied. Endpoint detection and response - EDR - as a category didn't really have a name yet when they started building it. The idea was: assume the attacker is already inside. Now what? You need to watch behavior, not just signatures. You need to understand the story a chain of events is telling, not just flag individual events. You need to hunt.

Yonatan spent eleven years as CTO, which in startup time is several careers. He watched the company scale from three people with a shared hypothesis to a global organization with customers across critical infrastructure, financial services, and government. He helped lead the team that achieved the best-ever results in the MITRE ATT&CK Enterprise Evaluation in 2022 - the closest thing the industry has to a standardized test for detection capabilities.

He also watched attackers get faster. Every year, the dwell time - the gap between when an attacker gets in and when defenders notice - shrank a little. But the defenders were still relying on humans to analyze alerts, humans to triage incidents, humans to decide what was real and what was noise. The throughput problem was getting worse, not better. There were simply too many alerts for too few analysts, and the analysts were burning out.

By 2023, he had an idea about how to fix that. It required starting over.

The Current Chapter

7AI:
The Agent
that Never Sleeps

In February 2024, Yonatan and Lior Div - same partner, same intensity, new problem - started 7AI in stealth. The thesis was simple and hard: the only way to close the attacker speed gap is to automate the entire incident-response workflow. Not parts of it. All of it.

When a threat appears in a modern enterprise network, a human analyst has to wake up, log in, pull context from a dozen different tools, figure out what's real, decide on a response, execute it, and document it. That process takes hours. An attacker with ransomware can encrypt a network in minutes.

7AI builds autonomous agents that do that entire workflow - triage, investigation, response, documentation - at machine speed. The humans step in only when the situation demands it: novel attack patterns, ethical judgment calls, high-stakes decisions with uncertain outcomes. Everything else runs without them.

By December 2025, 7AI had closed a $130 million Series A - led by Index Ventures and Blackstone Innovations Investments, with all seed investors following on. SecurityWeek called it the largest cybersecurity Series A on record. Fast Company named 7AI one of the world's most innovative security companies in their 2026 ranking. Both assessments landed within months of each other.

7AI Funding History
Seed Round
Announced Feb 2025
Greylock Partners · Spark Capital · CRV
$36M
Series A - Record-Breaking
December 2025
Index Ventures · Blackstone + all seed investors
$130M
Total Raised
Largest Cybersecurity Series A in History
$166M+
RECOGNITION
Fast Company Most Innovative Companies 2026
#6 in Security

The Timeline

Twenty-Five Years, No Straight Line

AGE ~12
First Hack. Reverse-engineers a video game to invert the cost function - buying items adds coins instead of subtracting them. Discovers that software is not magic, just logic that can be changed.
1998 - 2002
IDF Unit 8200. Recruited at 18 with no formal training. Spends four years in Israel's elite signals intelligence unit - the proving ground for the country's entire cybersecurity industry - learning offense from the ground up.
2002 - 2005
BSc, Hebrew University. Completes undergraduate degree in Computer Science and Mathematics. Takes the theory alongside the practice he's already accumulated.
2003 - 2004
Mobileye. Programmer and Algorithms Developer. Automotive computer vision - a completely different domain, same instinct for finding what's actually happening in noisy signal streams.
2005 - 2007
MSc in CS (Machine Learning), Hebrew University. The academic credential that would eventually put him in 784+ academic citations. His specialty: teaching machines to find patterns humans miss.
2006 - 2009
Gita Technologies. System Internals Development Team Lead at an Israeli intelligence and cyber R&D firm. Deep systems work, intelligence applications.
2009 - 2011
WatchDox, CTO. First CTO role. Leads R&D for a DRM and enterprise SaaS security startup. First taste of building product for commercial markets, not classified environments.
2012 - 2023
Cybereason, Co-Founder & CTO. Eleven years. Builds the company from a three-person hypothesis in Boston to a global EDR leader. Helps pioneer the endpoint detection and response category. Achieves best-ever MITRE ATT&CK evaluation results in 2022.
2024
7AI, Co-Founded. Launches in stealth with Lior Div. Raises $36M seed from Greylock, Spark Capital, and CRV to build autonomous AI agents for cyber incident response.
Feb 2025
7AI Emerges from Stealth. The company goes public with its mission and its $36M seed funding announcement.
Dec 2025
$130M Series A. Index Ventures and Blackstone Innovations Investments lead a round reported as the largest Series A in cybersecurity history. Fast Company names 7AI one of 2026's most innovative security companies.

Context

The Most Consequential Nine-Digit Number in Cybersecurity

Unit 8200 is Israel's signals intelligence corps. It reports to Israeli Military Intelligence and functions roughly the way NSA's Tailored Access Operations unit functions for the United States - elite technical personnel, classified missions, access to the most sophisticated offensive and defensive techniques their era can produce.

The unit recruits teenagers, typically through a combination of aptitude tests and direct talent spotting. Once in, recruits work on live systems with real stakes from very early in their service. The combination of high pressure, deep technical challenge, and early responsibility produces - with unusual frequency - the founders of cybersecurity companies.

Yonatan was recruited before he had taken a single university-level computer science course. He went in at 18 and came out four years later knowing how adversaries actually operate - not the theoretical version described in textbooks, but the operational version practiced by people whose jobs depend on it working.

That knowledge is the unfair advantage he's been spending his career converting into products.

Notable Unit 8200 Alumni in Tech
  • Gil Shwed - Co-Founder, Check Point Security
  • Tomer Weingarten - Co-Founder, SentinelOne
  • Nir Zuk - Founder, Palo Alto Networks
  • Lior Div - Co-Founder, Cybereason & 7AI
  • Yonatan Striem-Amit - Co-Founder, Cybereason & 7AI
  • Yossi Naar - Co-Founder, Cybereason

The Philosophy

Three Things He's Never Stopped Believing

△
Offense Teaches Defense
The only way to understand how attackers move is to think like one. Yonatan spent the first chapter of his career doing exactly that - in an intelligence unit where offense wasn't hypothetical. Twenty years later, every product he's built carries that fingerprint: start from what the attacker does, then work backward to what defense must provide.
■
Speed is the Whole Problem
Defenders aren't outthought. They're outraced. Attackers move in hours. Security teams move in days. The gap isn't intelligence, it's throughput. That's why 7AI is built around autonomous agents - not to remove humans from security, but to remove the part of the job that doesn't need human judgment and replace it with something that runs at network speed.
○
The Founding Partnership Matters
Yonatan and Lior Div have co-founded two consecutive companies together - Cybereason and 7AI. In a startup world that often treats founding partnerships as temporary arrangements, they've treated theirs as a long-term commitment. Both ventures were built from the same insight: the people who know how attacks actually work should be the ones building the defenses.
We're redrawing the line between what needs human brilliance and what machines can handle in security. By letting smart agents take care of the daily grind, we free our minds to do what they do best.

- Yonatan Striem-Amit on 7AI's mission

Notes from the Field

Things That Don't Fit Anywhere Else

🎮 The Game Hack - He didn't pick a lock or break into a school network. His first hack was a video game, and the exploit was elegant: make money go up when you spend it. The target was trivial. The method was not.
📚 784+ Citations - His work in Computer Science and Machine Learning has been cited in over 784 academic publications. For someone who primarily describes himself as a practitioner, that number suggests he's been thinking rigorously as well as practically.
🏗 Two Companies, One Partner - He and Lior Div co-founded Cybereason together in 2012, ran it for eleven years, left, and immediately started 7AI together in 2024. The security industry is full of serial founders. Not many repeat the same partnership.
📍 McLean, Virginia - He's based in McLean, VA - a town known primarily as the home of the CIA headquarters. Proximity to the US intelligence community is not an accident for someone building autonomous agents for national infrastructure defense.
⛳ RSA Committee Member - He reviews "Hackers and Threats" submissions for the RSA Conference - meaning he's one of the people who decides what the security industry considers worth saying at its biggest annual gathering.

In His Own Words

What He Actually Said

"With attackers harnessing the power of AI to unleash unprecedented levels of cyber assaults, the time has come to equip defenders with the same cutting-edge technology."
7AI Launch Statement, February 2025
"We're redrawing the line between what needs human brilliance and what machines can handle in security. By letting smart agents take care of the daily grind, we free our minds to do what they do best - tackle the wild, complex challenges that only human creativity can crack."
On 7AI's Agent Architecture
"Threat hunting relies on human intuition to discover threats - instead of using indicators of compromise and security tools. You need to understand the story that a chain of events tells."
Dark Reading Interview
"Traditional security teams remain static, often requiring years to adapt their tools. In contrast, attackers share exploits and test new methods within their communities almost overnight."
On the Defender Speed Problem

Academic Foundation

The Credentials Behind the Instincts

MSc Computer Science
Machine Learning Specialization
The Hebrew University of Jerusalem
2005 - 2007
BSc Computer Science + Mathematics
Double Major
The Hebrew University of Jerusalem
2002 - 2005
IDF Unit 8200
Signals Intelligence / Offensive Security
Israel Defense Forces
1998 - 2002

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