The rigor of an investigator, the independence of a lab.

Cybersecurity services, research & products, from Paris.

Featured paper: Time as a Key: Breaking Rhysida Ransomware

Sigreturn Labs

Services
Research
Products

Founder previously at

Europol
French Judicial Police
Quarkslab
Orange Cyberdefense
Digital Security

Trusted by

CEPOL
Certi-Trust
ECTEG

Senior security work.

Engagements deliver working code, reproducible findings and writeups.

Forensics

Post-compromise forensics, root-cause analysis and timeline reconstruction. Threat intelligence on the actors, infrastructure and malware involved.

Reverse engineering

Static and dynamic analysis of binaries, firmware and proprietary protocols. Malware analysis and decryption tooling.

Vulnerability research

Targeted auditing, fuzzing and code review to find unknown flaws. Proof-of-concept and working exploits, including modern mitigation bypasses on browsers, kernels and embedded systems.

Training

Malware analysis, taught from the basics: a self-paced online training whose first section is free to watch.

Public research.

11 advisories, two CVEs assigned in 2026 CVE-2026-54626 CVE-2026-54627 Papers All posts

Products.

Built in-house: our online training, an identity registrar and an app for iPhone and iPad.

Malware analysis and reverse engineering, online.

Online training, in video, at your own pace

The training runs from Windows internals to a final challenge: a ransomware program has encrypted four files, and you get them back.
- Windows internals
- Static and dynamic analysis
- Reverse engineering
- Debugging
- Cryptography
- Advanced techniques
- 201 video lessons
- 28 hours of video
- 22 labs solved on video
The author grades your report on the challenge by hand; once it is validated, you receive a certificate in your name that anyone can check online.

Go to the training
A specimen of the certificate. The QR code opens its public page.
dotID

Identity registrar for Polkadot and Kusama

Registrar #5 on Polkadot and #7 on Kusama, both seats granted by on-chain governance. dotID verifies the identity fields an account has set on chain, records the judgement on the People Chain, issues .id usernames, and publishes a directory of every verified identity.
dotid.app
WebDAV Manager

WebDAV client for iPhone and iPad

Browse, preview, upload and share the files on your own server, whether Nextcloud, a Synology NAS, Apache, IIS, rclone or dufs. First result for “WebDAV” on the US App Store, more than 23,000 downloads, no account needed, and the app collects nothing.
webdavman.com