These are the changes of ARK: Survival Evolved’s Patch 183.31, grouped into categories for clarity. If not otherwise indicated, they’re quoted from the relevant Steam Thread.

Bugfixes

• Fixed a client-side Crash with structure placing
• Eliminated some false-positives with underground-structure exploit detection (Behemoth Gates, etc)

(Original Announcement on Steam)

Here are the patchnotes of the previous patch (183.3)