diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6c27aca0a..a40e4d2d2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,16 @@
 
 All notable changes to this project will be documented in this file.
 
+## [4.2.29] - 2026-01-07
+
+### Security
+
+- Fix SSRF protection bypass ([GHSA](https://github.com/mastodon/mastodon/security/advisories/GHSA-xfrj-c749-jxxq))
+
+### Fixed
+
+- Fix mentions of domain-blocked users being processed (#37257 by @ClearlyClaire)
+
 ## [4.2.28] - 2025-12-08
 
 ### Security
diff --git a/app/services/process_mentions_service.rb b/app/services/process_mentions_service.rb
index f3fbb8021..391006a9a 100644
--- a/app/services/process_mentions_service.rb
+++ b/app/services/process_mentions_service.rb
@@ -69,7 +69,7 @@ class ProcessMentionsService < BaseService
     # Make sure we never mention blocked accounts
     unless @current_mentions.empty?
       mentioned_domains = @current_mentions.filter_map { |m| m.account.domain }.uniq
-      blocked_domains   = Set.new(mentioned_domains.empty? ? [] : AccountDomainBlock.where(account_id: @status.account_id, domain: mentioned_domains))
+      blocked_domains   = Set.new(mentioned_domains.empty? ? [] : AccountDomainBlock.where(account_id: @status.account_id, domain: mentioned_domains).pluck(:domain))
       mentioned_account_ids = @current_mentions.map(&:account_id)
       blocked_account_ids = Set.new(@status.account.block_relationships.where(target_account_id: mentioned_account_ids).pluck(:target_account_id))
 
diff --git a/docker-compose.yml b/docker-compose.yml
index 56fea4eec..eef22e1e3 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -56,7 +56,7 @@ services:
 
   web:
     build: .
-    image: ghcr.io/mastodon/mastodon:v4.2.28
+    image: ghcr.io/mastodon/mastodon:v4.2.29
     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:v4.2.28
+    image: ghcr.io/mastodon/mastodon:v4.2.29
     restart: always
     env_file: .env.production
     command: node ./streaming
@@ -95,7 +95,7 @@ services:
 
   sidekiq:
     build: .
-    image: ghcr.io/mastodon/mastodon:v4.2.28
+    image: ghcr.io/mastodon/mastodon:v4.2.29
     restart: always
     env_file: .env.production
     command: bundle exec sidekiq
diff --git a/lib/mastodon/version.rb b/lib/mastodon/version.rb
index 82638b53f..c95c0b39a 100644
--- a/lib/mastodon/version.rb
+++ b/lib/mastodon/version.rb
@@ -13,7 +13,7 @@ module Mastodon
     end
 
     def patch
-      28
+      29
     end
 
     def default_prerelease
diff --git a/spec/services/process_mentions_service_spec.rb b/spec/services/process_mentions_service_spec.rb
index 0db73c41f..cf5ffd1d1 100644
--- a/spec/services/process_mentions_service_spec.rb
+++ b/spec/services/process_mentions_service_spec.rb
@@ -8,9 +8,9 @@ RSpec.describe ProcessMentionsService, type: :service do
   let(:account) { Fabricate(:account, username: 'alice') }
 
   context 'when mentions contain blocked accounts' do
-    let(:non_blocked_account)          { Fabricate(:account) }
-    let(:individually_blocked_account) { Fabricate(:account) }
-    let(:domain_blocked_account)       { Fabricate(:account, domain: 'evil.com') }
+    let!(:non_blocked_account)          { Fabricate(:account) }
+    let!(:individually_blocked_account) { Fabricate(:account) }
+    let!(:domain_blocked_account)       { Fabricate(:account, domain: 'evil.com', protocol: :activitypub) }
     let(:status) { Fabricate(:status, account: account, text: "Hello @#{non_blocked_account.acct} @#{individually_blocked_account.acct} @#{domain_blocked_account.acct}", visibility: :public) }
 
     before do