diff --git a/build.sbt b/build.sbt
index 3b372a6..d0d8163 100644
--- a/build.sbt
+++ b/build.sbt
@@ -2,7 +2,7 @@ import scalapb.compiler.Version._
 import sbtrelease.ReleaseStateTransformations._
 import sbtcrossproject.CrossPlugin.autoImport.crossProject
 
-val Scala212 = "2.12.20"
+val Scala212 = "2.12.21"
 val Scala213 = "2.13.18"
 val Scala3 = "3.3.7"
 val scalatestVersion = "3.2.19"