Flatt Security
flatt.tech
Cloud Security
Application Security
Penetration Testing
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Financials
Funding and backers
Total raised
$1.8M
1 round on record
Latest round
$1.8M
Venture round · Oct 2021 · 5 yr ago
Team
11-50
employees, estimated range
The money's age
Long since its last round
60 months since the last round · not hiring
Momentum
15/100
in the news
Last sign of life
1 mo ago
a posting or a news item
The story so fareach stage dated by its source: the company's releases, the press, registers, filings
May 19, 2025
Launched on Hacker News Show HN: Takumi – An AI Security Engineer that found 10 zero-days (Vim, Next.js)
Dec 9, 2024
On the Hacker News front page Compromising OpenWrt Supply Chain · 584 points
Oct 18, 2021
Raised a round Venture round $1.8M · BRIDGE
2017
Founded
Tractionpublic signals, read monthly
Web presence
top 0.04%
of 133.2M domains by links, Common Crawl
Funding rounds
| Round | Date | Amount | Investors | Source |
|---|---|---|---|---|
| Venture round | Oct 2021 | $1.8M | — | BRIDGE |
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Overview
Flatt Security is a Tokyo cybersecurity company founded in 2017 that focuses on securing modern web and cloud applications. It provides manual penetration testing by engineers and develops Shisho Cloud, a product that scans code and infrastructure configuration. The company targets fast moving development teams rather than traditional enterprise audit cycles.
News
悪性パッケージ「ゼロ」の日はなし GMO Flatt Security「ソフトウェアサプライチェーン 脅威レポート 2026」公開
GMO Flatt Security株式会社は9月3日、ソフトウェアサプライチェーン攻撃の動向をまとめた調査レポート「ソフトウェアサプライチェーン 脅威レポート 2026」を公開した
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GMO Flatt Security、「ソフトウェアサプライチェーン 脅威レポート 2026」を公開
半年で悪性パッケージ約3万1,000件を検出・Takumi Guardは1日5,000万件超のパッケージダウンロードを検査 GMOインターネットグループで「エンジニアの背中を預かる」をミッションに、プロダクト開発組織に向けたサイバーセキュリ…
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Pwning Claude Code in 8 Different Ways
IntroductionHello, I'm RyotaK (@ryotkak), a security engineer at GMO Flatt Security Inc.A few months ago, I came across an interesting behavior while using Claude Code-it executed a command without my approval.Since I wasn't using the permission bypass mo
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Report
CVE-2025-59489: Arbitrary Code Execution in Unity Runtime
IntroductionHello, I'm RyotaK (@ryotkak), a security engineer at GMO Flatt Security Inc.In May 2025, I participated in the Meta Bug Bounty Researcher Conference 2025.During this event, I discovered a vulnerability (CVE-2025-59489) in the Unity Runtime tha
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Why XSS Persists in This Frameworks Era?
IntroductionHi, I'm canalun (@i_am_canalun), a security researcher at GMO Flatt Security Inc.This article explores the question: "Why Does XSS Still Occur So Frequently?" We will delve into why this notorious and classic vulnerability despite the widespre
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Cybersecurity AI Agent
Tuned by world-class offensive security experts, our AI agent, Takumi, uncovers critical vulnerabilities within your codebase that other tools miss, such as business logic bugs and broken authorizations. This allows you to receive actionable alerts with m
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Achieving RCE in famous Japanese chat tool with an obsolete Electron feature
IntroductionHello, I'm RyotaK (@ryotkak), a security engineer at GMO Flatt Security Inc.A while ago, I reported a remote code execution vulnerability that chains multiple problems in Chatwork, a popular communication tool in Japan.In the report that I sen
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Clone2Leak: Your Git Credentials Belong To Us
IntroductionHello, I'm RyotaK ( @ryotkak ), a security engineer at GMO Flatt Security Inc.In October 2024, I was hunting bugs for the GitHub Bug Bounty program. After investigating GitHub Enterprise Server for a while, I felt bored and decided to try to f
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Non-Intrusive Web Recon: Techniques from Chrome DevTools Recorder
Introduction: The Art of Non-Intrusive Web ReconHello, I'm pizzacat83 (@pizzacat83), a software engineer at Flatt Security Inc.When hunting for bugs, understanding the behavior of a target application is invaluable. The more knowledge you gain about the a
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Offices
Where the company hires and what each office is for
Cities
2
Hiring now
0
Countries
1
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Headquarters
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Tokyo
Japan
HQ
Shibuya
Japan
Regional office
桜丘町26-1 セルリアンタワー6階, 渋谷区, 東京都, 150-8512, JP
Financials
Total raised
$1.8M
Latest round
Venture - Series Unknown
Funding rounds
1
Funding rounds
| Round | Announced | Amount | |
|---|---|---|---|
| Venture - Series Unknown | 2021 | $1.8M | Details |