diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d687d52..6c3d4b0 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -15,7 +15,7 @@ jobs:
       fail-fast: false
       matrix:
         java: [ '17' ]
-        scala: [ '2.12.19', '2.13.16', '3.3.5' ]
+        scala: [ '2.12.21', '2.13.16', '3.3.5' ]
     steps:
       - uses: actions/checkout@v4
       - name: Setup Java
diff --git a/project/BuildHelper.scala b/project/BuildHelper.scala
index 52f2581..87a8e9b 100644
--- a/project/BuildHelper.scala
+++ b/project/BuildHelper.scala
@@ -4,7 +4,7 @@ import sbtbuildinfo._
 import BuildInfoKeys._
 
 object BuildHelper {
-  private val Scala212             = "2.12.19"
+  private val Scala212             = "2.12.21"
   private val Scala213             = "2.13.16"
   private val Scala3               = "3.3.5"
   private val KindProjectorVersion = "0.13.3"