diff --git a/config/src/main/java/org/springframework/security/config/annotation/AbstractConfiguredSecurityBuilder.java b/config/src/main/java/org/springframework/security/config/annotation/AbstractConfiguredSecurityBuilder.java
index 527eb84759f..3c80655261b 100644
--- a/config/src/main/java/org/springframework/security/config/annotation/AbstractConfiguredSecurityBuilder.java
+++ b/config/src/main/java/org/springframework/security/config/annotation/AbstractConfiguredSecurityBuilder.java
@@ -26,6 +26,7 @@
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.security.config.Customizer;
 import org.springframework.security.config.ObjectPostProcessor;
@@ -51,6 +52,7 @@
  * @param <B> The type of this builder (that is returned by the base class)
  * @author Rob Winch
  * @author DingHao
+ * @author Andrey Litvitski
  * @see WebSecurity
  */
 public abstract class AbstractConfiguredSecurityBuilder<O, B extends SecurityBuilder<O>>
@@ -101,7 +103,7 @@ protected AbstractConfiguredSecurityBuilder(ObjectPostProcessor<Object> objectPo
 	 * @return the result of {@link SecurityBuilder#build()} or {@link #getObject()}. If
 	 * an error occurs while building, returns null.
 	 */
-	public O getOrBuild() {
+	public @Nullable O getOrBuild() {
 		if (!isUnbuilt()) {
 			return getObject();
 		}
@@ -182,7 +184,7 @@ public <C> void setSharedObject(Class<C> sharedType, C object) {
 	 * @return the shared Object or null if it is not found
 	 */
 	@SuppressWarnings("unchecked")
-	public <C> C getSharedObject(Class<C> sharedType) {
+	public <C> @Nullable C getSharedObject(Class<C> sharedType) {
 		return (C) this.sharedObjects.get(sharedType);
 	}
 
@@ -276,7 +278,7 @@ public <C extends SecurityConfigurer<O, B>> C getConfigurer(Class<C> clazz) {
 	 * @return
 	 */
 	@SuppressWarnings("unchecked")
-	public <C extends SecurityConfigurer<O, B>> C removeConfigurer(Class<C> clazz) {
+	public <C extends SecurityConfigurer<O, B>> @Nullable C removeConfigurer(Class<C> clazz) {
 		List<SecurityConfigurer<O, B>> configs = this.configurers.remove(clazz);
 		if (configs == null) {
 			return null;
diff --git a/config/src/main/kotlin/org/springframework/security/config/annotation/web/HttpSecurityDsl.kt b/config/src/main/kotlin/org/springframework/security/config/annotation/web/HttpSecurityDsl.kt
index 5d25617b2b8..0277d427ad8 100644
--- a/config/src/main/kotlin/org/springframework/security/config/annotation/web/HttpSecurityDsl.kt
+++ b/config/src/main/kotlin/org/springframework/security/config/annotation/web/HttpSecurityDsl.kt
@@ -73,6 +73,7 @@ operator fun HttpSecurity.invoke(httpConfiguration: HttpSecurityDsl.() -> Unit)
  * in order to configure [HttpSecurity] using idiomatic Kotlin code.
  *
  * @author Eleftheria Stein
+ * @author Andrey Litvitski
  * @since 5.3
  * @param http the [HttpSecurity] which all configurations will be applied to
  * @param init the configurations to apply to the provided [HttpSecurity]
@@ -82,7 +83,7 @@ operator fun HttpSecurity.invoke(httpConfiguration: HttpSecurityDsl.() -> Unit)
 class HttpSecurityDsl(private val http: HttpSecurity, private val init: HttpSecurityDsl.() -> Unit) {
 
     var authenticationManager: AuthenticationManager? = null
-    val context: ApplicationContext = http.getSharedObject(ApplicationContext::class.java)
+    val context: ApplicationContext = http.getSharedObject(ApplicationContext::class.java)!!
 
     init {
         applyFunction1HttpSecurityDslBeans(this.context, this)