NebuSec

YC S26 · Active · Autonomous AI defense system for cyber attack

Competitors

Companies closest to NebuSec
Company	Category	Status	Program
Palitronica IncShared: cyber attack, security, systemActiveOther	Other	Active	YCW22
ZeroPathShared: bug bounty, cybersecurityActiveAI, Devtools	AI, Devtools	Active	YCS24
FederacyShared: bug bounty, securityInactiveDevtools	Devtools	Inactive	YCS18
TridentShared: cybersecurity, attack, defenseActiveAI	AI	Active	YCS26
XeolShared: cybersecurity, attack, blackAcquiredAI	AI	Acquired	YCS23

Adjacent

Companies next to NebuSec
Company	Category	Status	Program
TelivyShared: cybersecurityAcquiredOther	Other	Acquired	YCS21
Gecko SecurityShared: cybersecurity, attack, exploitingActiveAI	AI	Active	YCF24
CotoolShared: cybersecurityActiveAI	AI	Active	YCX25
Sublime BlackShared: cybersecurityInactiveAI	AI	Inactive	YCW19
RiotShared: securityActiveOther	Other	Active	YCW20

Also from S26 in AI

All of S26

Company	Category	Status
TraceforceCrowdStrike for AI AgentsActiveAI	AI	Active
CautionHosting platform for software you can't afford to have hackedActiveAI, Devtools	AI, Devtools	Active
ConiferLeast cost routing system to reduce 70%+ token spendActiveAI, Devtools	AI, Devtools	Active
DecaworkTraining company-specific models that approve AI actions.ActiveAI, Devtools	AI, Devtools	Active
FabraixThe world's frontier hacker of AI agents.ActiveAI	AI	Active
PalisadeAI that finds and fixes OS-level vulnerabilities across device fleetsActiveAI	AI	Active

Founders

Eten ZouFounder/CEO
Yuan TanFounder/CTO
Frank WuFounder/COO
Xiaochuan YuFounder/VP of Vulnerability Research

About NebuSec

NebuSec is founded by the world’s #1 hacking team. We were the first team to build an nginx RCE and the first to root Android 17. Our co-founders include members of the world’s No. 1 CTF team, DEF CON winners, Black Hat speakers, and PhD in cybersecurity. We have won $400K in bug bounties by exploiting the Linux kernel and Chrome browser. “Audited by NebuSec” is a mark of serious security credibility: a signal to customers, investors, and partners that your product has been reviewed by the world’s best hackers.

YC batch: S26 · Summer 2026
Status, per YC: Active
Category: AI
Team size: 4
Location: San Francisco, CA, USA; Remote
Founded: 2026
Checked: 33m ago

YC tags: Artificial Intelligence, B2B, Security, Cybersecurity, Enterprise

NebuSec in S26: 231 companies, 88% AI

NebuSec: questions

Which YC batch was NebuSec in?

NebuSec was in Y Combinator's Summer 2026 batch (S26).

Is NebuSec still active?

Y Combinator lists NebuSec as active.

Who founded NebuSec?

NebuSec's founders, as listed on its YC page: Eten Zou (Founder/CEO), Yuan Tan (Founder/CTO), Frank Wu (Founder/COO), Xiaochuan Yu (Founder/VP of Vulnerability Research).

Where is NebuSec based?

NebuSec lists San Francisco, CA, USA; Remote as its location on YC's directory.

Sources: each program's public company list, read twice a week. Not affiliated with Y Combinator or any other program. Logos via logo.dev; trademarks belong to their owners.