diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4a5f5c5282..f2d898cb06 100755
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -24,6 +24,9 @@
 * 【core   】      修复`Validator.isBetween`在高精度Number类型下存在精度丢失问题（pr#4136@Github）
 * 【core   】      修复`FileNameUtil.extName`在特殊后缀判断逻辑过于宽松导致误判问题（pr#4142@Github）
 * 【core   】      修复`TypeUtil.getClass`无法识别`GenericArrayType`问题（pr#4138@Github）
+* 【core   】      修复`CreditCodeUtil.randomCreditCode`部分字母未使用问题（pr#4149@Github）
+* 【core   】      修复`CacheableAnnotationAttribute`可能并发问题（pr#4149@Github）
+* 【core   】      修复`URLUtil.url`未断开连接问题（pr#4149@Github）
 
 -------------------------------------------------------------------------------------------------------------
 # 5.8.41(2025-10-12)
diff --git a/hutool-core/src/main/java/cn/hutool/core/annotation/CacheableAnnotationAttribute.java b/hutool-core/src/main/java/cn/hutool/core/annotation/CacheableAnnotationAttribute.java
index 5ef49f1ec8..f1a1cf71a6 100644
--- a/hutool-core/src/main/java/cn/hutool/core/annotation/CacheableAnnotationAttribute.java
+++ b/hutool-core/src/main/java/cn/hutool/core/annotation/CacheableAnnotationAttribute.java
@@ -15,7 +15,7 @@ import java.lang.reflect.Method;
 public class CacheableAnnotationAttribute implements AnnotationAttribute {
 
 	private volatile boolean valueInvoked;
-	private Object value;
+	private volatile Object value;
 
 	private boolean defaultValueInvoked;
 	private Object defaultValue;
diff --git a/hutool-core/src/main/java/cn/hutool/core/util/CreditCodeUtil.java b/hutool-core/src/main/java/cn/hutool/core/util/CreditCodeUtil.java
index 4e40ea612c..d51f920c3f 100755
--- a/hutool-core/src/main/java/cn/hutool/core/util/CreditCodeUtil.java
+++ b/hutool-core/src/main/java/cn/hutool/core/util/CreditCodeUtil.java
@@ -100,7 +100,7 @@ public class CreditCodeUtil {
 
 		//
 		for (int i = 0; i < 2; i++) {
-			int num = RandomUtil.randomInt(BASE_CODE_ARRAY.length - 1);
+			int num = RandomUtil.randomInt(BASE_CODE_ARRAY.length);
 			buf.append(Character.toUpperCase(BASE_CODE_ARRAY[num]));
 		}
 		for (int i = 2; i < 8; i++) {
@@ -108,7 +108,7 @@ public class CreditCodeUtil {
 			buf.append(BASE_CODE_ARRAY[num]);
 		}
 		for (int i = 8; i < 17; i++) {
-			int num = RandomUtil.randomInt(BASE_CODE_ARRAY.length - 1);
+			int num = RandomUtil.randomInt(BASE_CODE_ARRAY.length);
 			buf.append(BASE_CODE_ARRAY[num]);
 		}
 
diff --git a/hutool-core/src/main/java/cn/hutool/core/util/URLUtil.java b/hutool-core/src/main/java/cn/hutool/core/util/URLUtil.java
index f8aca116ec..14887e118e 100644
--- a/hutool-core/src/main/java/cn/hutool/core/util/URLUtil.java
+++ b/hutool-core/src/main/java/cn/hutool/core/util/URLUtil.java
@@ -807,8 +807,9 @@ public class URLUtil extends URLEncodeUtil {
 		} else {
 			// 如果资源打在jar包中或来自网络，使用网络请求长度
 			// issue#3226, 来自Spring的AbstractFileResolvingResource
+			URLConnection con = null;
 			try {
-				final URLConnection con = url.openConnection();
+				con = url.openConnection();
 				useCachesIfNecessary(con);
 				if (con instanceof HttpURLConnection) {
 					final HttpURLConnection httpCon = (HttpURLConnection) con;
@@ -817,6 +818,10 @@ public class URLUtil extends URLEncodeUtil {
 				return con.getContentLengthLong();
 			} catch (final IOException e) {
 				throw new IORuntimeException(e);
+			} finally {
+				if (con instanceof HttpURLConnection) {
+					((HttpURLConnection) con).disconnect();
+				}
 			}
 		}
 	}