---
title: "Breaking: #88646 - Removed inheritance of AbstractService from AbstractAuthenticationService"
manual: "TYPO3 Core Changelog"
version: "main"
permalink: "https://docs.typo3.org/permalink/changelog:breaking-88646"
source: "Changelog/10.0/Breaking-88646-RemovedInheritanceOfAbstractServiceFromAbstractAuthenticationService.rst"
modified: "2026-09-15T10:46:36+00:00"
---

# Breaking: #88646 - Removed inheritance of AbstractService from AbstractAuthenticationService

See [forge#88646](https://forge.typo3.org/issues/88646)

## Description

The PHP `\TYPO3\CMS\Core\Authentication\AbstractAuthenticationService` class is used for any kind of Authentication
or Authorization towards Backend Users and Frontend Users.

It was previously based on `\TYPO3\CMS\Core\Service\AbstractService` for any kind of Service API, which
also includes manipulating files and execution of external applications, which is
there for legacy reasons since TYPO3 3.x, where the Service API via `GeneralUtility::makeInstanceService` was added.

In order to refactor the Authentication API, the `\TYPO3\CMS\Core\Authentication\AbstractAuthenticationService`
class does not inherit from `\TYPO3\CMS\Core\Service\AbstractService` anymore. Instead, the most required
methods for executing a service is added to the Abstract class directly.

## Impact

Any calls or checks on the `\TYPO3\CMS\Core\Authentication\AbstractAuthenticationService` class or methods, properties or constants that reside within
`\TYPO3\CMS\Core\Service\AbstractService` will result in PHP `E_ERROR` or `E_WARNING`.

Since `\TYPO3\CMS\Core\Authentication\AbstractAuthenticationService` is used for most custom Authentication APIs,
this could affect some of the hooks or custom authentication providers available.

## Affected Installations

TYPO3 installations that have custom Authentication providers for frontend or backend
users / groups - e.g. LDAP or Two-Factor-Authentication.

## Migration

If your custom Authentication Service extends from `\TYPO3\CMS\Core\Authentication\AbstractAuthenticationService`
but requires methods or properties from `\TYPO3\CMS\Core\Service\AbstractService`, ensure to copy over the
necessary methods/properties/constants into your custom Authentication provider.