# apereo/cas

Apereo CAS - Identity & Single Sign On for all earthlings and beyond.

Repository: https://github.com/apereo/cas
Canonical: https://ross.abutalabs.com/products/cas
Homepage: https://apereo.github.io/cas/
Language: Java
License: Apache-2.0
License Family: permissive
Topics: sso-authentication, authentication, authorization, java, websso, saml2, oauth2, openidconnect, ldap-authentication, spring-boot, spring-webflow, spring-cloud, spring-framework, identity-provider, duosecurity, sso, open-source, aws, mfa, fido
Last push: 2026-08-26T12:37:35+00:00

## Health v2 (maintenance only)
Score: 99/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 98, longevity 100
- inputs: {"age_days": 5473, "days_push": 7, "days_rel": 19, "gap_med": 26, "n_releases_24m": 36}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 11360, forks 3957 (observed 2026-08-28T04:10:46.842355+00:00)

## What it is
Apereo CAS is an enterprise open-source identity provider and single sign-on server implemented in Java on Spring Boot. It centralizes authentication and authorization for web applications, supporting protocols like CAS, SAML2, OAuth2, and OpenID Connect, plus MFA and LDAP integration.

## Use cases
- implement single sign-on across multiple web applications
- act as a SAML2 or OpenID Connect identity provider
- add multi-factor authentication to enterprise logins
- authenticate users against LDAP or Active Directory
- centralize OAuth2 authorization for internal services
- replace ad-hoc per-app login systems with one identity platform

## When to choose
- you need a mature, self-hosted SSO identity server supporting many protocols
- your organization requires MFA, delegated authn, and fine-grained authorization policies
- you want an open-source alternative to commercial IdPs like Okta or Ping

## When to avoid
- you only need simple session auth for a single small application
- your team cannot operate a JVM-based server with significant configuration overhead
- you need a lightweight embedded auth library rather than a standalone server

## Facets
- artifact type: service
- maturity: stable
- function: auth, authorization, http-server, security
- domain: security, web-development, backend, self-hosted
- platform: jvm, self-hosted
- tags: sso, saml2, oauth2, openid-connect, identity-provider, mfa, ldap, spring-boot, enterprise, web-server, docker

## Member repositories
- apereo/cas (main) score 99

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:10:46.842355+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:15:42.032355+00:00, confidence not recorded.
  - readme: https://github.com/apereo/cas (fetched 2026-08-28T04:10:46.842355+00:00, sha 59fe1e4e6e2a)
  - homepage: https://apereo.github.io/cas/ (fetched 2026-08-29T08:14:28.344806+00:00, sha 3ac6d62d1283)
- Data as of 2026-08-30T08:39:29.467469+00:00.