About

About

Kazuma Matsumoto

Security engineer working in offensive security, independently conducting vulnerability research on open-source software and widely deployed applications. This blog documents my findings and analysis.

Work Experience

Current

GMO Cybersecurity by Ierae, Inc.

  • Offensive Security Department, Advanced Assessment Section (May 2026–)

    Web application penetration testing and adversarial evaluation of large language models (LLMs).

  • Assessment Service Department (Aug 2024 – Apr 2026)

    Identifying vulnerabilities across web applications, mobile APIs, and HTTP-layer anti-cheat mechanisms in mobile games.

Previous

Ministry of Defense, Japan (2024)

  • Served as Technical Officer at the Self-Defense Forces Cyber Defense Command under the Joint Staff.

CVEs

CVE Target Type
CVE-2026-20943 Microsoft Office Click-to-Run elevation of privilege
CVE-2025-23358 NVIDIA App Installer privilege escalation
CVE-2026-22561 Anthropic Claude Desktop Installer privilege escalation
CVE-2026-25075 strongSwan Integer underflow in EAP-TTLS AVP parser
CVE-2026-32854 LibVNCServer Null pointer dereference in HTTP proxy handlers
CVE-2026-5720 miniupnpd Integer underflow in SOAPAction header parsing
CVE-2026-28525 SWUpdate Integer underflow in multipart upload parser

Interests

  • AI security
  • AI-assisted code analysis
  • Web application security
  • Windows internals
  • Linux internals