diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/SecurityProperties.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/SecurityProperties.java
index e5b9357077..48f766f955 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/SecurityProperties.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/SecurityProperties.java
@@ -36,7 +36,7 @@ import org.springframework.util.StringUtils;
  * @author Dave Syer
  * @author Andy Wilkinson
  */
-@ConfigurationProperties(prefix = "security", ignoreUnknownFields = false)
+@ConfigurationProperties(prefix = "security")
 public class SecurityProperties implements SecurityPrerequisite {
 
 	/**