Blog
Articles, tutorials, and field notes on identity, integration, API management, and application security — spanning nearly two decades of hands-on work.
Practical Business Continuity
For the small business owner, should the power going out mean you can’t make money? Should the computer system going down for 20 minutes mean a restaurant can’t take or cook orders any longer? Some basic level of preparation for anything other than ideal circumstances and commonsense needs to be…
Static Credentials Must Not Be Used In The Browser
Authentication is described in this post.
Datastore Security Requirements
This post will introduce a generic set of database / datastore security requirements that be used as a starting point when developing a database security strategy.
Application Front-Ends Must Not Make Authorization Decisions
First, let’s get the usual introductions out of the way. For an in-depth discussion of what Authorization is, check out this post. For a complete introduction to Authorization concepts see my Authorization Series. This post continues my long-running Authorization Series. In this post, we’re going…
API Gateways and Multiple Consumer Types
Sometimes at client sites, I see a separation of APIs advertised on an API Gateway based upon consumer type. Sometimes, this is unavoidable, but there should be a core set of APIs and a general push to create APIs that are reusable. Reusability of APIs is a foundational building block of API…
RFC 9068: A JWT-Based OAuth2 Access Token Format Standard
For anyone who has been paying attention, this blog post has been a long-time coming for multiple reasons. First, this is my first blog post in a couple of years — I’ve been heads down on a couple of projects for awhile now. This is literally the first time I’ve “come up for air” since the last…
Making Authorization Decisions
This blog post continues our discussion of Authorization in the API space. It will explore common authorization patterns with API Gateways and the backend API Providers. Generally, the API Gateway will apply a Coarse Grained Authorization (CGA) decision and the API Provider will implement Fine…
Delegation — A General Discussion
This blog post expands on delegation and related concepts introduced in my Kerberos Delegation blog post. It also brings together two blog series I’ve been working on over the years: SAML2 vs. JWT Series and Kerberos and Windows Security Series. Delegation is a critical building block of end-to-end…
Kerberos and Windows Security: Delegation
In this next post in the Kerberos and Windows Security Series, we are going to explore a very useful, but abstract feature of the Kerberos Authentication Protocol: Delegation. In particular, we are going to focus on the Windows implementation of this feature. Delegation allows downstream actors to…
HTTP POST vs GET: Is One More Secure For Use In REST APIs?
The use of HTTP POST vs HTTP GET for read-only (or query) operations in REST APIs recently came up in a conversation. For this particular shop, there had been a long-standing ban on the use of GET requests for use in homegrown applications. This had been the case since before REST APIs were in…
OAuth2 Access Tokens vs API Keys — Using JWTs
There are several approaches to securing APIs. Every API Gateway vendor supports the same core set of API security mechanisms. API Keys and OAuth2 are two examples of these authentication (plus authorization) mechanism. When should one be used over the other? What are the differences between the…
Identity Protocols, Hosted Login UIs, and Custom Login UIs
There are many ways to implement user authentication in a modern application (mobile, desktop, tablet, web, etc). I have previously explored Authentication, Federation, and SSO; that post introduces several key concepts that are assumed here. At the intersection of user experience, authentication,…