diff --git a/config/src/main/java/org/springframework/security/config/annotation/web/configuration/WebSecurityConfiguration.java b/config/src/main/java/org/springframework/security/config/annotation/web/configuration/WebSecurityConfiguration.java
index 03942c41d4..7e506d8d02 100644
--- a/config/src/main/java/org/springframework/security/config/annotation/web/configuration/WebSecurityConfiguration.java
+++ b/config/src/main/java/org/springframework/security/config/annotation/web/configuration/WebSecurityConfiguration.java
@@ -33,7 +33,6 @@ import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.config.BeanDefinition;
-import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
 import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
 import org.springframework.beans.factory.support.BeanDefinitionBuilder;
 import org.springframework.beans.factory.support.BeanDefinitionRegistry;
@@ -79,6 +78,7 @@ import org.springframework.web.filter.ServletRequestPathFilter;
  *
  * @author Rob Winch
  * @author Keesun Baik
+ * @author Yanming Zhou
  * @since 3.2
  * @see EnableWebSecurity
  * @see WebSecurity
@@ -190,7 +190,7 @@ public class WebSecurityConfiguration implements ImportAware {
 	}
 
 	@Bean
-	public static BeanFactoryPostProcessor conversionServicePostProcessor() {
+	public static RsaKeyConversionServicePostProcessor conversionServicePostProcessor() {
 		return new RsaKeyConversionServicePostProcessor();
 	}
 
diff --git a/config/src/main/java/org/springframework/security/config/annotation/web/reactive/WebFluxSecurityConfiguration.java b/config/src/main/java/org/springframework/security/config/annotation/web/reactive/WebFluxSecurityConfiguration.java
index be6052224d..c4ac08ef1b 100644
--- a/config/src/main/java/org/springframework/security/config/annotation/web/reactive/WebFluxSecurityConfiguration.java
+++ b/config/src/main/java/org/springframework/security/config/annotation/web/reactive/WebFluxSecurityConfiguration.java
@@ -21,7 +21,6 @@ import java.util.List;
 
 import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
@@ -44,6 +43,7 @@ import static org.springframework.security.config.Customizer.withDefaults;
 
 /**
  * @author Rob Winch
+ * @author Yanming Zhou
  * @since 5.0
  */
 @Configuration(proxyBeanMethods = false)
@@ -100,7 +100,7 @@ class WebFluxSecurityConfiguration {
 	}
 
 	@Bean
-	static BeanFactoryPostProcessor conversionServicePostProcessor() {
+	static RsaKeyConversionServicePostProcessor conversionServicePostProcessor() {
 		return new RsaKeyConversionServicePostProcessor();
 	}