diff --git a/build.gradle b/build.gradle
index 29e8a80b..881fb85e 100644
--- a/build.gradle
+++ b/build.gradle
@@ -5,7 +5,7 @@ buildscript {
         junit5PlatformVersion = '1.10.0'
 
         slf4jVersion = '2.0.7' // http://www.slf4j.org/download.html
-        log4jVersion = '2.20.0' // https://logging.apache.org/log4j/2.x/javadoc.html
+        log4jVersion = '2.21.0' // https://logging.apache.org/log4j/2.x/javadoc.html
         // Note: Since Jackson 2.14, Android SDK 26 is required
         // https://github.com/FasterXML/jackson/wiki/Jackson-Releases
         jacksonVersion = '2.15.2' // https://github.com/FasterXML/jackson-databind/tags