TYPO3 10.4.3 and 9.5.18 maintenance releases published

Categories: Development Created by Oliver Hader
The versions 10.4.3 and 9.5.18 of the TYPO3 Enterprise Content Management System have just been released.

The following TYPO3 updates have been released:

  • TYPO3 10.4.3 LTS
  • TYPO3 9.5.18 LTS

Both versions are maintenance releases only. They aim to reduce and fix side-effects of recent TYPO3 v10.4.2 and v9.5.17 releases.

Further upgrade instructions

Upgrade Wizard - Manual actions required

Sites that were upgraded from an older TYPO3 version to TYPO3 v9 LTS before version 9.5.11 (<9.5.11) most probably require the invocation of "Update backend user configuration array" upgrade wizard - this can be done in the backend interface at Admin Tools > Upgrade > Upgrade Wizard. This wizard was introduced with TYPO3 v9.5.11, the necessity to run it was not emphasized enough back then.


TYPO3 can be installed in various ways. For example the traditional way by using the source package at get.typo3.org or the modern way by setting up a project using composer, to name just two. Further details can be found in the according release notes:

Details on side-effects in previous relases

  • change for TYPO3-CORE-SA-2020-004 caused side-effects on extension- or user-land code interacting with caches in Extbase, showing deserialization errors for ReflectionService (see Forge issue #91404)
  • change for TYPO3-CORE-SA-2020-005 causes side-effects for sites that were upgraded from versions before TYPO3 v8 and were upgrade before TYPO3 v9.5.11, e.g. causing problems in the page-tree (see Forge issue #91407)
    • $BE_USER->uc probably can contain class references to stdClass which need to be converted
    • TYPO3 v9.5.11 add a corresponding Update backend user configuration array upgrade wizard
    • to be found at Admin Tools > Upgrade > Upgrade Wizard > Update backend user configuration array
  • change for TYPO3-CORE-SA-2020-006 introduced a strict referrer check, blocking cross-site requests and thus also blocking single-sign-on (SSO) implementations (see Forge issue #91396)