diff --git a/CHANGELOG.md b/CHANGELOG.md
index 028f89a51..a348aabc6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,8 @@
 ## 4.6.4
 
 ### 新特性
+* 【http】         自动关闭HttpURLConnection的头安全检查（issue#512@Github）
+* 【setting】     Setting变量替换支持从系统参数中取值
 
 ### Bug修复
 * 【db】           解决ThreadLocalConnection多数据源被移除问题（pr#66@Gitee）
diff --git a/hutool-http/src/main/java/cn/hutool/http/GlobalHeaders.java b/hutool-http/src/main/java/cn/hutool/http/GlobalHeaders.java
index 10f1e88e1..6c933ab13 100644
--- a/hutool-http/src/main/java/cn/hutool/http/GlobalHeaders.java
+++ b/hutool-http/src/main/java/cn/hutool/http/GlobalHeaders.java
@@ -37,6 +37,10 @@ public enum GlobalHeaders {
 	 * @return this
 	 */
 	public GlobalHeaders putDefault(boolean isReset) {
+		// 解决HttpURLConnection中无法自定义Host等头信息的问题
+		// https://stackoverflow.com/questions/9096987/how-to-overwrite-http-header-host-in-a-httpurlconnection/9098440
+		System.setProperty("sun.net.http.allowRestrictedHeaders", "true");
+		
 		if (isReset) {
 			this.headers.clear();
 		}
diff --git a/hutool-setting/src/main/java/cn/hutool/setting/SettingLoader.java b/hutool-setting/src/main/java/cn/hutool/setting/SettingLoader.java
index c416836a6..8706baee5 100644
--- a/hutool-setting/src/main/java/cn/hutool/setting/SettingLoader.java
+++ b/hutool-setting/src/main/java/cn/hutool/setting/SettingLoader.java
@@ -201,22 +201,23 @@ public class SettingLoader {
 		for (String var : vars) {
 			key = ReUtil.get(reg_var, var, 1);
 			if (StrUtil.isNotBlank(key)) {
-				// 查找变量名对应的值
+				// 本分组中查找变量名对应的值
 				String varValue = this.groupedMap.get(group, key);
-				if (null != varValue) {
-					// 替换标识
-					value = value.replace(var, varValue);
-				} else {
-					// 跨分组查找
+				// 跨分组查找
+				if (null == varValue) {
 					final List<String> groupAndKey = StrUtil.split(key, CharUtil.DOT, 2);
 					if (groupAndKey.size() > 1) {
 						varValue = this.groupedMap.get(groupAndKey.get(0), groupAndKey.get(1));
-						if (null != varValue) {
-							// 替换标识
-							value = value.replace(var, varValue);
-						}
 					}
 				}
+				// 系统参数中查找
+				if(null == varValue) {
+					varValue = System.getProperty(key);
+				}
+				if (null != varValue) {
+					// 替换标识
+					value = value.replace(var, varValue);
+				}
 			}
 		}
 		return value;