This set of releases includes a high severity security patch (see: https://www.silverstripe.org/download/security-releases/). We recommend you upgrade as soon as possible. More information:
https://docs.silverstripe.org/en/4/changelogs/4.3.1
https://docs.silverstripe.org/en/4/changelogs/4.2.4
https://docs.silverstripe.org/en/4/changelogs/4.1.5
https://docs.silverstripe.org/en/4/changelogs/4.0.7
https://docs.silverstripe.org/en/4/changelogs/3.7.3
https://docs.silverstripe.org/en/4/changelogs/3.6.7