DIVER OSINT CTF 2026 "cooking" Writeup
Table of Contents
This article was automatically translated from Japanese by AI.
Challenge
DIVER OSINT CTF 2026 “cooking”
Solution
Searching for "ボリス・ジョンソン 来日 料理" leads to a Facebook post by the cooking school’s operator.
The Facebook profile identifies the company as Kyoto-based 株式会社のぞみ (Nozomi Co., Ltd.). A Google search leads to its gBizINFO company profile, while the National Tax Agency Corporate Number Publication Site confirms the unique 13-digit Corporate Number 5130001026308.
According to the National Tax Agency’s explanation, a 13-digit Corporate Number consists of a leading check digit followed by the 12-digit Corporate Identification Number. Removing the leading 5 from 5130001026308 gives 130001026308.
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Diver26{130001026308}