diff --git a/Gemfile b/Gemfile
index fba7371b64..b64a1dbe91 100644
--- a/Gemfile
+++ b/Gemfile
@@ -14,6 +14,7 @@ gem 'haml-rails', '~>2.0'
 gem 'pg', '~> 1.5'
 gem 'pghero'
 
+gem 'aws-sdk-core', '< 3.216.0', require: false # TODO: https://github.com/mastodon/mastodon/pull/34173#issuecomment-2733378873
 gem 'aws-sdk-s3', '~> 1.123', require: false
 gem 'blurhash', '~> 0.1'
 gem 'fog-core', '<= 2.6.0'
diff --git a/Gemfile.lock b/Gemfile.lock
index 05536976ea..0c2915988a 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -95,14 +95,13 @@ GEM
     attr_required (1.0.2)
     aws-eventstream (1.3.2)
     aws-partitions (1.1066.0)
-    aws-sdk-core (3.220.1)
+    aws-sdk-core (3.215.1)
       aws-eventstream (~> 1, >= 1.3.0)
       aws-partitions (~> 1, >= 1.992.0)
       aws-sigv4 (~> 1.9)
-      base64
       jmespath (~> 1, >= 1.6.1)
-    aws-sdk-kms (1.99.0)
-      aws-sdk-core (~> 3, >= 3.216.0)
+    aws-sdk-kms (1.96.0)
+      aws-sdk-core (~> 3, >= 3.210.0)
       aws-sigv4 (~> 1.5)
     aws-sdk-s3 (1.177.0)
       aws-sdk-core (~> 3, >= 3.210.0)
@@ -922,6 +921,7 @@ DEPENDENCIES
   active_model_serializers (~> 0.10)
   addressable (~> 2.8)
   annotaterb (~> 4.13)
+  aws-sdk-core (< 3.216.0)
   aws-sdk-s3 (~> 1.123)
   better_errors (~> 2.9)
   binding_of_caller (~> 1.0)