diff --git a/configs/components/rubygem-concurrent-ruby.rb b/configs/components/rubygem-concurrent-ruby.rb
index 9fa6d9bd5..3869cc8ac 100644
--- a/configs/components/rubygem-concurrent-ruby.rb
+++ b/configs/components/rubygem-concurrent-ruby.rb
@@ -4,6 +4,8 @@
   pkg.version version
 
   case version
+  when '1.2.3'
+    pkg.sha256sum '82fdd3f8a0816e28d513e637bb2b90a45d7b982bdf4f3a0511722d2e495801e2'
   when '1.3.3'
     pkg.sha256sum '4f9cd28965c4dcf83ffd3ea7304f9323277be8525819cb18a3b61edcb56a7c6a'
   else