diff --git a/CHANGELOG.md b/CHANGELOG.md
index 35ad9caea..5a1f06599 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,7 +6,23 @@ All notable changes to this project will be documented in this file.
 ## End of life notice
 
 **The 4.0.x branch will not receive any update after 2023-10-31.**
-This means that no security fix will be made available for this branch after this date, and you will need to update to a more recent version (such as the 4.1.x branch) to receive security fixes.
+This means that no security fix will be made available for this branch after this date, and you will need to update to a more recent version (such as the 4.2.x branch) to receive security fixes.
+
+## [4.0.12] - 2023-10-10
+
+### Changed
+
+- Change some worker lock TTLs to be shorter-lived ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/27246))
+- Change user archive export allowed period from 7 days to 6 days ([suddjian](https://github.com/mastodon/mastodon/pull/27200))
+
+### Fixed
+
+- Fix mentions being matched in some URL query strings ([mjankowski](https://github.com/mastodon/mastodon/pull/25656))
+- Fix multiple instances of the trend refresh scheduler sometimes running at once ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/27253))
+- Fix importer returning negative row estimates ([jgillich](https://github.com/mastodon/mastodon/pull/27258))
+- Fix filtering audit log for entries about disabling 2FA ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/27186))
+- Fix tIME chunk not being properly removed from PNG uploads ([TheEssem](https://github.com/mastodon/mastodon/pull/27111))
+- Fix inefficient queries in “Follows and followers” as well as several admin pages ([ClearlyClaire](https://github.com/mastodon/mastodon/pull/27116), [ClearlyClaire](https://github.com/mastodon/mastodon/pull/27306))
 
 ## [4.0.11] - 2023-09-20
 
diff --git a/docker-compose.yml b/docker-compose.yml
index dbe314a12..db2f81d20 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -56,7 +56,7 @@ services:
 
   web:
     build: .
-    image: ghcr.io/mastodon/mastodon:v4.0.11
+    image: ghcr.io/mastodon/mastodon:v4.0.12
     restart: always
     env_file: .env.production
     command: bash -c "rm -f /mastodon/tmp/pids/server.pid; bundle exec rails s -p 3000"
@@ -77,7 +77,7 @@ services:
 
   streaming:
     build: .
-    image: ghcr.io/mastodon/mastodon:v4.0.11
+    image: ghcr.io/mastodon/mastodon:v4.0.12
     restart: always
     env_file: .env.production
     command: node ./streaming
@@ -95,7 +95,7 @@ services:
 
   sidekiq:
     build: .
-    image: ghcr.io/mastodon/mastodon:v4.0.11
+    image: ghcr.io/mastodon/mastodon:v4.0.12
     restart: always
     env_file: .env.production
     command: bundle exec sidekiq
diff --git a/lib/mastodon/version.rb b/lib/mastodon/version.rb
index f4fb2dd88..d586fa9e3 100644
--- a/lib/mastodon/version.rb
+++ b/lib/mastodon/version.rb
@@ -13,7 +13,7 @@ module Mastodon
     end
 
     def patch
-      11
+      12
     end
 
     def flags