UniAuth
UniAuth Blog

Engineering, security, and product updates

Deep dives into how we build a security-first identity provider. Post-quantum crypto, privacy engineering, and hard-won lessons from production.

Engineering posts

Engineering8 min

Your Browser Updated. Why Did That Sign You Out?

Sessions were being terminated as suspected theft when nothing had been stolen. The cause was a session fingerprint that included the browser's version number, so a routine auto-update looked identical to an attacker replaying a stolen cookie from a different machine. Here is why the check was wrong, and what replaced it.

UniAuth EngineeringAugust 6, 2026
Engineering10 min

Push Approvals Without a Push Vendor

Push-based two-factor usually means handing a third party a channel into your users' devices. Web Push with VAPID does not require that. We built approve-or-deny as a second factor on the open standard, and the hard parts turned out to be the approval screen and the polling endpoint, not the cryptography.

UniAuth EngineeringMay 26, 2026
Engineering18 min

Building a DNS-Rebinding-Safe HTTP Client

Webhook delivery and SCIM provisioning both require outbound HTTP requests to user-supplied URLs. We built an SSRF-resistant HTTP client that validates resolved IPs after DNS lookup but before connection. This post covers the pitfalls of naive URL parsing and the dual-stack IPv4/IPv6 edge cases we caught.

UniAuth EngineeringFebruary 5, 2026
Engineering9 min

SCIM 2.0 Multi-Tenant Isolation: Design Decisions

When multiple organizations share a UniAuth deployment, their SCIM group memberships must be strictly isolated. We discuss the schema design that gives each tenant its own namespace, the bearer-token-per-client auth model, and how bulk operations respect tenant boundaries without sacrificing throughput.

UniAuth EngineeringJanuary 18, 2026

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