Projects
- Mijn SimyoSeveral critical and high-severity vulnerabilities in the Mijn Simyo app and API, reported to KPN-CERT.Coordinated disclosureCERT#2026052777000311
- Target
- Mijn Simyo app and API
- Vendor
- Simyo (KPN)
- Reported to
- KPN-CERT
- Reported
- May 2026
- Severity
- Critical and high
KPN-CERT Hall of Fame
- HomelabA Proxmox VE homelab at home for Linux administration, virtualisation and Python automation.
- packets.shBilingual portfolio site with its own admin behind a password and TOTP, self-hosted.Response headers from packets.shdefault values
200 OK
- strict-transport-security
- max-age=63072000; includeSubDomains
- content-security-policy
- default-src 'self'; img-src 'self' data:; font-src 'self'; object-src 'none'; base-uri 'none'; form-action 'self'; script-src 'self' 'sha256-…'
- x-frame-options
- DENY
- x-content-type-options
- nosniff
- referrer-policy
- strict-origin-when-cross-origin
- cross-origin-opener-policy
- same-origin
- permissions-policy
- camera=(), microphone=(), geolocation=()
Coordinated disclosureCERT#2026052777000311
- Target
- Mijn Simyo app and API
- Vendor
- Simyo (KPN)
- Reported to
- KPN-CERT
- Reported
- May 2026
- Severity
- Critical and high
Response headers from packets.shdefault values
200 OK
- strict-transport-security
- max-age=63072000; includeSubDomains
- content-security-policy
- default-src 'self'; img-src 'self' data:; font-src 'self'; object-src 'none'; base-uri 'none'; form-action 'self'; script-src 'self' 'sha256-…'
- x-frame-options
- DENY
- x-content-type-options
- nosniff
- referrer-policy
- strict-origin-when-cross-origin
- cross-origin-opener-policy
- same-origin
- permissions-policy
- camera=(), microphone=(), geolocation=()
Experience
- Support and helpdesk technicianNedsoft B.V.Sep 2026 – present
- IT Support InternNedsoft B.V.Mar 2026 – Sep 2026
- ICT InternNXT GEN ICT B.V.Oct 2025 – Feb 2026
- Work experience placementStichting DajongFeb 2024 – Aug 2024
Education
- IT systems and devices technician (MBO level 3)Techniek College Rotterdam2024 – 2026
Skills
- Infrastructure
- Virtualisation (Proxmox VE), Docker, device deployment, Git
- Operating systems
- Linux administration, Windows administration, Active Directory, Microsoft 365
- Networking & programming
- Networking, Python, Bash
- Security
- Cybersecurity, vulnerability assessment, web application security
- Works at
- Nedsoft B.V.
- Based in
- Rotterdam, the Netherlands
- Studies
- MBO 3, IT systems & devices
- Languages
- Dutch (native), English (fluent)
Profile
Graduated as an IT systems and devices technician (MBO level 3) from Techniek College Rotterdam, focused on systems and networks. Since September 2026 I have worked as a support and helpdesk technician at Nedsoft B.V., where I was an intern before. Security has always been my hobby: I have reported several vulnerabilities through coordinated disclosure. At home I run a Proxmox VE homelab, where I work on Linux administration, virtualisation and Python automation.
Certification and disclosure
Certifications
- Linux EssentialsLinux Professional Institute (LPI), ID LPI000688496Jun 2026
Disclosures
- Mijn Simyo app and APISimyo (KPN), KPN-CERT Hall of FameMay 2026