diff --git a/Gemfile.lock b/Gemfile.lock
index eaf7e06..7822a4b 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -2,7 +2,7 @@ PATH
   remote: .
   specs:
     maxmind-geoip2 (1.4.0)
-      connection_pool (~> 2.2)
+      connection_pool (>= 2.2, < 4.0)
       http (>= 4.3, < 6.0)
       maxmind-db (~> 1.4)
 
@@ -13,7 +13,7 @@ GEM
       public_suffix (>= 2.0.2, < 8.0)
     ast (2.4.3)
     bigdecimal (3.3.1)
-    connection_pool (2.5.5)
+    connection_pool (3.0.1)
     crack (1.0.1)
       bigdecimal
       rexml
diff --git a/maxmind-geoip2.gemspec b/maxmind-geoip2.gemspec
index 3326c6b..deb5f08 100644
--- a/maxmind-geoip2.gemspec
+++ b/maxmind-geoip2.gemspec
@@ -26,7 +26,7 @@ Gem::Specification.new do |s|
   }
   s.required_ruby_version = '>= 3.2'
 
-  s.add_dependency 'connection_pool', ['~> 2.2']
+  s.add_dependency 'connection_pool', '>= 2.2', '< 4.0'
   s.add_dependency 'http', '>= 4.3', '< 6.0'
   s.add_dependency 'maxmind-db', ['~> 1.4']