Center of expertise in cybersecurity CESTI & PASSI

Comprehensive technical and organizational support for your cybersecurity projects

Technical safety audits

Audits are one of the cornerstones of cybersecurity and one of our daily activities.

PASSI qualified audits

ACCEIS is qualified as an Information Systems Security Audit Provider by ANSSI. A guarantee of our technical excellence and the professionalism of our methodologies.

Red Team Audit

The Red Team aims to achieve its objectives, using various techniques validated with the client (logical or physical intrusion, social engineering, phishing, etc.).

Safety governance

We help your CISOs and CIOs to implement a comprehensive security management approach within your company. For efficient and effective use of your information system.

ISMS implementation

Bringing your ISMS to life means taking action, monitoring and adapting to change. Organization is key, and we can help you with that.

Risk & compliance

We support you in assessing threats and detecting vulnerabilities to guarantee information security and protect your organization’s sensitive data.

A Breton imprint

ACCEIS is a recognized player at regional level in Brittany, then nationally with a branch in Paris.

A native cybersecurity center of expertise, rooted from the outset in the Breton ecosystem, the cradle of cybersecurity in France.

Based in Rennes and Paris (rue de Rennes), we work all over France with major private and public economic players.

A Breton creation

ACCEIS is a recognized regional and national player in the cybersecurity community. By flying the Breton flag, we’re further anchoring our values of excellence, passion, sincerity and proximity, and showing our origins loud and clear.

Cybersecurity Bretagne Rennes Paris

Partners and sponsors of cybersecurity events

From Paris to Rennes, we’re on the cyber scene, so come and join us at our events!

They testify for ACCEIS!

Your content goes here. Edit or remove this text inline or in the Content settings module. You can also style every aspect of this content in the module Design settings and even apply custom CSS to this text in the module Advanced settings.

Extraire un .git depuis une vulnérabilité Path Traversal

Dans le cadre d'un audit de sécurité d'un site web, il est courant de ne pas avoir accès au code source de l'application auditée (boîte noire). Cette situation est souvent contraignante, car le temps limité de l'audit peut être gaspillé sur des fonctionnalités qui...

How to crack encrypted SSH private keys?

This article will look at various techniques for breaking SSH private keys. An unencrypted private key can be used by anyone with access to the file. An encrypted key, on the other hand, can only be used by those who know the password needed to decrypt the key. Thus,...

Comment casser des clés privées SSH chiffrées

Cet article va aborder différentes techniques de cassage de clés privées SSH. Une clé privée non chiffrée peut être utilisée par n'importe qui ayant accès au fichier. Alors qu'une clé chiffrée, elle, ne sera utilisable que par les personnes connaissant le mot de passe...

LostCertificate | Writeup challenge leHack2024 (Crypto)

À l'occasion du salon leHack 2024, un challenge sur les courbes elliptiques a été proposé lors du CTF. Cet article va présenter les différentes pistes que j'ai explorées lors de la compétition puis une méthode de résolution de ce challenge. Ce challenge est le seul...

CSRF GET + SameSite – Attaque concrète

Afin de prévenir les attaques CSRF (Cross-Site Request Forgery), les bonnes pratiques de sécurité, comme celles de l'OWASP, recommandent l'utilisation d'un modèle de jeton de synchronisation ou jeton anti-CSRF. L'absence de jeton n'entraîne pas nécessairement une...

CSRF GET + SameSite – Concrete attack

In order to prevent CSRF (Cross-Site Request Forgery) attacks, security best practices such as those of OWASP recommend the use of a synchronization token model or anti-CSRF token. The absence of a token does not necessarily lead to vulnerability, and several factors...

A look back at Insomni’hack 2024

Insomni'hack is a cybersecurity conference founded and organized by SCRT S.A. (now Orange Cyberdefense Switzerland) since 2008. It takes place in Switzerland, and lasts a week for each edition. This year, it took place from April 22 to 26, 2024 at the SwissTech...

eBPF program creation in practice – PID concealment (Part 1)

This article is a tutorial on how to create an eBPF program using a tracepoint. If you're not familiar with eBPF, you can refer to our introduction to eBPF, or to the official documentation What is a tracepoint? How do I create one with eBPF? What are the steps...

eBPF par la pratique – Dissimulation d’un PID (Partie 1)

Cet article est un tutoriel pour réaliser un programme eBPF en utilisant un tracepoint. Si vous n'êtes pas familié avec l'eBPF, vous pouvez vous référer à notre introduction à l'eBPF, ou à la documentation officiel Qu'est-ce qu'un tracepoint ? Comment le créer avec...

Introduction to eBPF

Are you familiar with eBPF ? Do you know its purpose or how it works ? Today, I'm trying to outline a brief overview of what, for me, is a revolutionary and very promising technology for the future of computing. eBPF is a revolutionary technology with origins in the...