diff --git a/CHANGELOG.md b/CHANGELOG.md
index d8e82f1..43de0ce 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,7 +3,7 @@
 All notable changes to this project will be documented in this file.
 
 ## [unreleased]
-- Switched to scala-2.12.20
+- Switched to scala-2.12.21
 - Switched to scala-2.13.18
 - Switched to scala-3.7.4
 - Switched to scalajs-1.20.1
diff --git a/build.sbt b/build.sbt
index 767b101..26fccc6 100644
--- a/build.sbt
+++ b/build.sbt
@@ -2,7 +2,7 @@ import sbtcrossproject.CrossPlugin.autoImport.crossProject
 
 lazy val scala210 = "2.10.7"
 lazy val scala211 = "2.11.12"
-lazy val scala212 = "2.12.20"
+lazy val scala212 = "2.12.21"
 lazy val scala213 = "2.13.18"
 lazy val scala3 = "3.7.4"