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Startups14,448Programs29

14,448 startups · 29 programs

NebuSec

Active · Autonomous AI defense system for cyber attack

WebsiteYC profile

Why it ranks

How the rank works
8signal of 100 · rising 8
  • went through YCProgram · this site+4
  • team of 4Team size · YC's directory+3.6

A sum of public facts, not a judgement and not investment advice.

Competitors

OtherPalitronica IncShared: cyber attack, security, systemYC W22KitchenerStartup →Developer toolsInactiveFederacyShared: bug bounty, securityYC S18San FranciscoStartup →AIZeroPathShared: bug bounty, cybersecurityYC S24San FranciscoStartup →AITridentShared: cybersecurity, attack, defenseYC S26San FranciscoStartup →
Companies closest to NebuSec
Company
Palitronica IncShared: cyber attack, security, systemYC W22ActiveOther
FederacyShared: bug bounty, securityYC S18InactiveDevtools
ZeroPathShared: bug bounty, cybersecurityYC S24ActiveAI, Devtools
TridentShared: cybersecurity, attack, defenseYC S26ActiveAI

Adjacent

AIAcquiredXeolShared: cybersecurity, attack, blackYC S23New York CityStartup →OtherAcquiredTelivyShared: cybersecurityYC S21San FranciscoStartup →AIGecko SecurityShared: cybersecurity, attack, exploitingYC F24LondonStartup →AICotoolShared: cybersecurity, attackYC X25San FranciscoStartup →OtherRiotShared: securityYC W20ParisStartup →
Companies next to NebuSec
Company
XeolShared: cybersecurity, attack, blackYC S23AcquiredAI
TelivyShared: cybersecurityYC S21AcquiredOther
Gecko SecurityShared: cybersecurity, attack, exploitingYC F24ActiveAI
CotoolShared: cybersecurity, attackYC X25ActiveAI
RiotShared: securityYC W20ActiveOther

Also from S26 in AI

All of S26
AITraceforceCrowdStrike for AI AgentsYC S26San FranciscoStartup →AICautionHosting platform for software you can't afford to have hackedYC S26George TownStartup →AIConiferIntelligent decisions for critical AI operationsYC S26San FranciscoStartup →AIDecaworkTraining company-specific models that approve AI actions.YC S26San FranciscoStartup →AIFabraixThe world's frontier hacker of AI agents.YC S26San FranciscoStartup →AIPalisadeAI that finds and fixes OS-level vulnerabilities across device fleetsYC S26San FranciscoStartup →
Company
TraceforceCrowdStrike for AI Agentsteam of 2ActiveAI
CautionHosting platform for software you can't afford to have hackedteam of 5ActiveAI, Devtools
ConiferIntelligent decisions for critical AI operationsteam of 4ActiveAI, Devtools
DecaworkTraining company-specific models that approve AI actions.2 programsteam of 2ActiveAI, Devtools
FabraixThe world's frontier hacker of AI agents.team of 2ActiveAI
PalisadeAI that finds and fixes OS-level vulnerabilities across device fleetsActiveAI

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
6h ago

YC tags: B2B, Security, Cybersecurity, Enterprise, AI

Changes seen

TagsOct 19, 2026

Newly tagged AI; no longer tagged Artificial Intelligence.

Source ↗

NebuSec in S26: 229 companies, 88% AI

LinkedIn

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.