62 posts tagged with "keycloak"

Everything you can do in the Phase Two console, you can now do from code.

Create a dedicated Keycloak cluster. Add a realm to it. Attach a custom domain and watch the certificate get issued. Upload a custom provider. Restrict the admin console to your office IP range. Pull yesterday's logs.

Three things shipped together, because none of them is much use alone: the Management API, the API credentials that authenticate to it, and a Terraform provider generated from the same spec.

All three are experimental for now. The console marks API credentials as such, and the Terraform provider is at 0.1.0. Point them at test environments rather than production while the surface settles.

We're shipping an experimental Telemetry Export for Enterprise Keycloak clusters. Point it at your own OTLP endpoint and your cluster's Keycloak logs and authentication events start arriving in whatever you already run — OpenSearch, Datadog, Grafana, SigNoz, Elastic, or your own OpenTelemetry Collector.

No agent to install, no log shipper to configure, and nothing to run on your side except the collector you already have.

Bottom line: upgrade this week if your login page or SAML endpoints are reachable from the internet, or if you run stateless mode on MySQL/MariaDB. Otherwise take it in your normal cycle. Keycloak 26.7.4 fixes six CVEs — five published as high, one medium. Two of them let an unauthenticated attacker exhaust memory and crash the server by hitting endpoints that are open by definition. One breaking change, in Authorization Services URI matching.

A Keycloak CORS error is almost never a CORS-configuration problem in the general sense. There is no CORS server setting to turn on. Keycloak decides per request by comparing the browser's Origin header against the Web Origins list on the OIDC client named in that request, using exact string matching. If it matches, the response carries Access-Control-Allow-Origin. If it does not, you get 403 with the body {"error":"Invalid origin"} — and the browser reports it as a CORS failure, which sends most people to the wrong place.

So the first thing to do is not to read a CORS guide. It is to open the Network tab, find the failing request, and check whether the status is 403 with that body. That single fact splits every cause below into two halves.

A Keycloak production readiness checklist has to answer two different questions, and most published ones only answer the first. Keycloak's start command refuses to boot until you settle two things, and it prints a clear error for each, so those are easy. The harder list is everything it will happily let you ship wrong: brute force protection is off, your audit log accepts forged IP addresses from anyone, event tables grow forever, and the readiness endpoint disagrees with your load balancer for the first few seconds of every restart.

Everything below was run against quay.io/keycloak/keycloak:26.7.3. Where a number appears, it came out of a terminal, not from memory.

Keycloak returns invalid_grant for at least eight unrelated failures, and the error code itself tells you nothing. The useful field is error_description, which Keycloak fills in with a short string that maps almost one-to-one onto a cause:

{"error":"invalid_grant","error_description":"Code not valid"}

invalid_grant is OAuth's designated bucket for "the grant you presented is no good", so Keycloak uses it for expired codes, replayed codes, PKCE mismatches, rotated refresh tokens, dead sessions, revoked offline tokens, and bad passwords alike. Read the description, find it in the table below, stop guessing.

Everything here was run against Keycloak 26.7.3 on 2026-09-07, with realm defaults except where a test says otherwise.

Today we're launching keycloak-skills — an open-source Agent Skills plugin that teaches Claude how to configure Keycloak correctly — and the Phase Two Keycloak MCP server, 158 admin tools that let it do the work against a live cluster instead of just telling you what to type.

Two commands to install. Works against any Keycloak — and gets sharper the closer you get to ours. Don't have a Keycloak yet? The agent can provision one for you and it's free for 30 days.

Custom domains on Phase Two can now serve the files iOS and Android use to link a domain to a mobile app. Upload them from the dashboard and they are live in minutes — no deploy, no cluster restart.

That closes a gap that had nothing to do with Keycloak's capabilities and everything to do with where Keycloak sits in a mobile login flow.

SCIM — System for Cross-domain Identity Management — is a standard REST API for creating, updating, and deactivating user accounts across systems. SSO answers "can this person log in?" SCIM answers "does this person have an account at all, and should they still?"

If you sell to enterprises, you will be asked for it. This post covers what it is, when you actually need it, and a working walkthrough of Keycloak's native SCIM API — which arrived as a preview feature and is not enabled by default.

Everything here was run against Keycloak 26.7.3.

We're open-sourcing keycloak-atomic-auth-flows, a Keycloak extension that replaces an entire set of authentication flows, authenticator configs, and their bindings in one atomic, transactional request.

It was built in partnership with Gusto, who use Keycloak for user authentication and rely on Phase Two for enterprise Keycloak support. It has been running in their production environment for almost a year. The public repository is the extraction of that work into a standalone extension anyone can install.