diff --git a/lib/gitlab/ldap/access.rb b/lib/gitlab/ldap/access.rb
index 518955bd24..5a4add79c8 100644
--- a/lib/gitlab/ldap/access.rb
+++ b/lib/gitlab/ldap/access.rb
@@ -31,13 +31,13 @@ module Gitlab
         return true unless Gitlab.config.ldap['group_base'].present?
 
         # Get LDAP user entry
-        ldap_user = Gitlab::LDAP::Person.find_by_dn(user.extern_uid)
+        ldap_user = Gitlab::LDAP::Person.find_by_dn(user.extern_uid, adapter)
 
         # Get all GitLab groups with activated LDAP
         groups = ::Group.where('ldap_cn IS NOT NULL')
 
         # Get LDAP groups based on cn from GitLab groups
-        ldap_groups = groups.pluck(:ldap_cn).map { |cn| Gitlab::LDAP::Group.find_by_cn(cn) }
+        ldap_groups = groups.pluck(:ldap_cn).map { |cn| Gitlab::LDAP::Group.find_by_cn(cn, adapter) }
         ldap_groups = ldap_groups.compact.uniq
 
         # Iterate over ldap groups and check user membership
diff --git a/lib/gitlab/ldap/group.rb b/lib/gitlab/ldap/group.rb
index 61cab8393c..b7af14e225 100644
--- a/lib/gitlab/ldap/group.rb
+++ b/lib/gitlab/ldap/group.rb
@@ -7,8 +7,9 @@
 module Gitlab
   module LDAP
     class Group
-      def self.find_by_cn(cn)
-        Gitlab::LDAP::Adapter.new.group(cn)
+      def self.find_by_cn(cn, adapter=nil)
+        adapter ||= Gitlab::LDAP::Adapter.new
+        adapter.group(cn)
       end
 
       def initialize(entry)