// Cesium    EST. 2026

Research.
Build.
Protect.

Cesium is an independent group focused on security research, privacy advocacy, and open-source development. We document vulnerabilities under responsible disclosure, build useful tools, and help individuals reclaim their digital privacy.

READ RESEARCH → ABOUT US
FOCUS AREAS
Security · Privacy · Development
DISCLOSURE POLICY
Responsible Disclosure (90-day)
CONTACT
security@wearecesium.org
STATUS
Active · Accepting Reports
// 001    WHAT WE DO
// 01   SECURITY
Security Research

We document vulnerabilities and run responsible disclosure research across platforms, services, and software. All findings are coordinated with vendors before publication under a 90-day disclosure window.

// 02   DEVELOPMENT
Development

We build open-source tools, utilities, and applications that serve the security and privacy communities. Practical software that solves real problems — released under permissive licenses.

// 03   PRIVACY
Privacy

We provide clear, actionable information on online privacy, FOSS alternatives, and digital self-defense. No jargon — practical guides for individuals who want to take back control of their data.

// 002    DISCLOSURE PHILOSOPHY

We disclose responsibly.
Always.

Every vulnerability we find is reported to the affected vendor first. We give a minimum of 90 days for a fix before any public disclosure. Security research only improves the ecosystem when it's done with care — not for clout.

90
DAY DISCLOSURE WINDOW
100%
OPEN SOURCE TOOLS
0
VENDOR EXCEPTIONS
CVE
COORDINATED SUBMISSIONS
// 003    LATEST FROM THE BLOG
SECURITY BLOG → PRIVACY BLOG →
// ABOUT CESIUM

An independent group that takes security seriously.

Cesium was founded by a small group of security researchers, developers, and privacy advocates who wanted to build something honest — a place to publish real research, ship useful tools, and help people understand the threats they face online.

// PRINCIPLES
We operate in public.

Transparency is the baseline. Our research is published in full. Our tools are open source. Our disclosure process is documented and enforced without exceptions.

We don't take bug bounties for research we consider in the public interest. We don't accept vendor payments for positive coverage. We don't sit on vulnerabilities.

If we find something, we tell the vendor. If the vendor doesn't respond or doesn't fix it, we tell everyone else.

// WHAT DRIVES US
RESPONSIBLE DISCLOSURE
We follow a strict 90-day disclosure policy. Vendors are notified privately and given a reasonable window to patch. Extensions are granted case-by-case for complex issues. There are no exceptions for companies that simply prefer silence.
OPEN SOURCE FIRST
Every tool we build is released under a permissive open-source license. We believe security tooling shouldn't be locked behind enterprise contracts or opacity. If the code is useful, it should be available.
PRIVACY AS A RIGHT
Online privacy isn't a luxury feature — it's a baseline right that has been steadily eroded. We publish practical, non-commercial guidance on how to reclaim it, without affiliate links or sponsored recommendations.
NO SENSATIONALISM
We don't name vulnerabilities. We don't build landing pages for CVEs. We write clearly, cite our work, and let the findings speak for themselves. Security theatre helps nobody.
// THE TEAM

A small, distributed group. Some of us prefer to stay pseudonymous — this is the security world, after all.

CS
t4
FOUNDER · DEVELOPER · SECURITY RESEARCHER

Web application security, tool development and responsible disclosure coordination. Has reported to a number of platforms under responsible disclosure.

// SECURITY RESEARCH

Vulnerability
Research & Advisories

All findings published here have been disclosed to vendors prior to publication. CVE IDs are linked where assigned.

// PRIVACY BLOG

Privacy Guides
& Analysis

Practical, non-commercial guides on digital privacy, FOSS alternatives, and reclaiming control of your data. No affiliate links. No sponsored content.