Struts2 高危漏洞修复方案 (S2-016/S2-017)
近期Struts2被曝重要漏洞，此漏洞影响struts2.0-struts2.3所有版本，可直接导致服务器被远程控制从而引起数据泄漏,影响巨大,受影响站点以电商、银行、门户、政府居多.
引发的威胁：
取得网站服务器主机管理权限。
CVSS：(AV:R/AC:L/Au:NR/C:C/A:C/I:C/B:N)score:10.00（最高10分，高危）
即：远程攻击、攻击难度低、不需要用户认证，对机密性、完整性、可用性均构成完全影响。
验证情况：
Struts2漏洞利用工具下载:http://download.csdn.net/detail/mydwr/6921681
验证如下：
图1 网站目录
图2 成功执行ipconfig命令
图3成功硬盘目录
官方描述：
S2-016：https://cwiki.apache.org/confluence/display/WW/S2-016
S2-017：https://cwiki.apache.org/confluence/display/WW/S2-017
官方建议修复方案：升级到最新版本 struts-2.3.15.1
但通常现有系统升级，可能导致不稳定及与其他框架比如spring等的不兼容，成本较高。
鉴于此csdn网友jzshmyt整理了一种既可以不用升级现有struts版本，有能完美解决这两个漏洞的方案，
分享如下：
-------------------------
第1步.下载http://download.csdn.net/detail/mydwr/6921817
第2步.解压,将src目录中的所有文件,复制到自己项目的src目录中，编译通过,形成class文件
(本例struts是Struts-core-2.1.6版本_对2.0-2.3版本都有效,实际项目需要根据struts版本做适当调整）.
应用服务器会优先加载class目录中的类，自动覆盖jar包中的类.
第3步.web.xml中配置com.htht.commonweb.listener.MyServletContextListener
- <listener>
- <listener-class>org.hdht.commonweb.listener.MyServletContextListenerlistener-class>
- listener>
第4步.重启服务,修复完毕.
附：com.htht.commonweb.listener.MyServletContextListener.java，完整包参见struts2_S016_S017_repair.rar解压目录
启动漏洞监听
-------------------------
package com.htht.commonweb.listener;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import com.htht.commonweb.JavaEEbugRepair;
/**
* WEB应用程序初始化监听器
*/
public class MyServletContextListener implements ServletContextListener {
public void contextDestroyed(ServletContextEvent arg0) {
}
public void contextInitialized(ServletContextEvent arg0) {
try {
JavaEEbugRepair.initRepair_S2_016();
JavaEEbugRepair.initRepair_S2_017();
} catch (Exception e) {
e.printStackTrace();
}
}
}
附：ognl.Ognl.java，完整包参见struts2_S016_S017_repair.rar解压目录
ognl调用解决漏洞
package ognl;
import java.io.StringReader;
import java.util.Map;
import com.htht.commonweb.JavaEEbugRepair;
public abstract class Ognl
{
public static Object parseExpression(String expression)
throws OgnlException
{
if(JavaEEbugRepair.repair_s2_016(expression)){
return null;
}
try {
OgnlParser parser = new OgnlParser(new StringReader(expression));
return parser.topLevelExpression();
} catch (ParseException e) {
throw new ExpressionSyntaxException(expression, e);
} catch (TokenMgrError e) {
throw new ExpressionSyntaxException(expression, e);
}
}
public static Map createDefaultContext(Object root)
{
return addDefaultContext(root, null, null, null, new OgnlContext());
}
public static Map createDefaultContext(Object root, ClassResolver classResolver)
{
return addDefaultContext(root, classResolver, null, null, new OgnlContext());
}
public static Map createDefaultContext(Object root, ClassResolver classResolver, TypeConverter converter)
{
return addDefaultContext(root, classResolver, converter, null, new OgnlContext());
}
public static Map createDefaultContext(Object root, ClassResolver classResolver, TypeConverter converter, MemberAccess memberAccess)
{
return addDefaultContext(root, classResolver, converter, memberAccess, new OgnlContext());
}
public static Map addDefaultContext(Object root, Map context)
{
return addDefaultContext(root, null, null, null, context);
}
public static Map addDefaultContext(Object root, ClassResolver classResolver, Map context)
{
return addDefaultContext(root, classResolver, null, null, context);
}
public static Map addDefaultContext(Object root, ClassResolver classResolver, TypeConverter converter, Map context)
{
return addDefaultContext(root, classResolver, converter, null, context);
}
public static Map addDefaultContext(Object root, ClassResolver classResolver, TypeConverter converter, MemberAccess memberAccess, Map context)
{
OgnlContext result;
if (!(context instanceof OgnlContext)) {
result = new OgnlContext();
result.setValues(context);
} else {
result = (OgnlContext)context;
}
if (classResolver != null) {
result.setClassResolver(classResolver);
}
if (converter != null) {
result.setTypeConverter(converter);
}
if (memberAccess != null) {
result.setMemberAccess(memberAccess);
}
result.setRoot(root);
return result;
}
public static void setClassResolver(Map context, ClassResolver classResolver)
{
context.put("_classResolver", classResolver);
}
public static ClassResolver getClassResolver(Map context)
{
return (ClassResolver)context.get("_classResolver");
}
public static void setTypeConverter(Map context, TypeConverter converter)
{
context.put("_typeConverter", converter);
}
public static TypeConverter getTypeConverter(Map context)
{
return (TypeConverter)context.get("_typeConverter");
}
public static void setMemberAccess(Map context, MemberAccess memberAccess)
{
context.put("_memberAccess", memberAccess);
}
public static MemberAccess getMemberAccess(Map context)
{
return (MemberAccess)context.get("_memberAccess");
}
public static void setRoot(Map context, Object root)
{
context.put("root", root);
}
public static Object getRoot(Map context)
{
return context.get("root");
}
public static Evaluation getLastEvaluation(Map context)
{
return (Evaluation)context.get("_lastEvaluation");
}
public static Object getValue(Object tree, Map context, Object root)
throws OgnlException
{
return getValue(tree, context, root, null);
}
public static Object getValue(Object tree, Map context, Object root, Class resultType)
throws OgnlException
{
OgnlContext ognlContext = (OgnlContext)addDefaultContext(root, context);
Object result = ((Node)tree).getValue(ognlContext, root);
if (resultType != null) {
result = getTypeConverter(context).convertValue(context, root, null, null, result, resultType);
}
return result;
}
public static Object getValue(String expression, Map context, Object root)
throws OgnlException
{
return getValue(expression, context, root, null);
}
public static Object getValue(String expression, Map context, Object root, Class resultType)
throws OgnlException
{
return getValue(parseExpression(expression), context, root, resultType);
}
public static Object getValue(Object tree, Object root)
throws OgnlException
{
return getValue(tree, root, null);
}
public static Object getValue(Object tree, Object root, Class resultType)
throws OgnlException
{
return getValue(tree, createDefaultContext(root), root, resultType);
}
public static Object getValue(String expression, Object root)
throws OgnlException
{
return getValue(expression, root, null);
}
public static Object getValue(String expression, Object root, Class resultType)
throws OgnlException
{
return getValue(parseExpression(expression), root, resultType);
}
public static void setValue(Object tree, Map context, Object root, Object value)
throws OgnlException
{
OgnlContext ognlContext = (OgnlContext)addDefaultContext(root, context);
Node n = (Node)tree;
n.setValue(ognlContext, root, value);
}
public static void setValue(String expression, Map context, Object root, Object value)
throws OgnlException
{
setValue(parseExpression(expression), context, root, value);
}
public static void setValue(Object tree, Object root, Object value)
throws OgnlException
{
setValue(tree, createDefaultContext(root), root, value);
}
public static void setValue(String expression, Object root, Object value)
throws OgnlException
{
setValue(parseExpression(expression), root, value);
}
public static boolean isConstant(Object tree, Map context) throws OgnlException
{
return ((SimpleNode)tree).isConstant((OgnlContext)addDefaultContext(null, context));
}
public static boolean isConstant(String expression, Map context) throws OgnlException
{
return isConstant(parseExpression(expression), context);
}
public static boolean isConstant(Object tree) throws OgnlException
{
return isConstant(tree, createDefaultContext(null));
}
public static boolean isConstant(String expression) throws OgnlException
{
return isConstant(parseExpression(expression), createDefaultContext(null));
}
public static boolean isSimpleProperty(Object tree, Map context) throws OgnlException
{
return ((SimpleNode)tree).isSimpleProperty((OgnlContext)addDefaultContext(null, context));
}
public static boolean isSimpleProperty(String expression, Map context) throws OgnlException
{
return isSimpleProperty(parseExpression(expression), context);
}
public static boolean isSimpleProperty(Object tree) throws OgnlException
{
return isSimpleProperty(tree, createDefaultContext(null));
}
public static boolean isSimpleProperty(String expression) throws OgnlException
{
return isSimpleProperty(parseExpression(expression), createDefaultContext(null));
}
public static boolean isSimpleNavigationChain(Object tree, Map context) throws OgnlException
{
return ((SimpleNode)tree).isSimpleNavigationChain((OgnlContext)addDefaultContext(null, context));
}
public static boolean isSimpleNavigationChain(String expression, Map context) throws OgnlException
{
return isSimpleNavigationChain(parseExpression(expression), context);
}
public static boolean isSimpleNavigationChain(Object tree) throws OgnlException
{
return isSimpleNavigationChain(tree, createDefaultContext(null));
}
public static boolean isSimpleNavigationChain(String expression) throws OgnlException
{
return isSimpleNavigationChain(parseExpression(expression), createDefaultContext(null));
}
}附：com.htht.commonweb.JavaEEbugRepair.java，完整包参见struts2_S016_S017_repair.rar解压目录
拦截攻击关键代码
OgnlRuntime.setMethodAccessor(Runtime.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(System.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(ProcessBuilder.class,new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(OgnlRuntime.class, new NoMethodAccessor());
//io敏感操作
OgnlRuntime.setMethodAccessor(OutputStream.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(InputStream.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(File.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(DataOutput.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(DataInput.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(Reader.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(Writer.class, new NoMethodAccessor()); -------------------------
package com.htht.commonweb;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.File;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.Reader;
import java.io.Writer;
import java.util.Map;
import ognl.MethodAccessor;
import ognl.MethodFailedException;
import ognl.OgnlRuntime;
/**
* @author yanjianzhong([email protected]) 2013/08/08
* @版权所有,转载请标明出处. http://blog.csdn.net/jzshmyt
* download : http://jskfs.googlecode.com/files/struts2_(016_017)_bug_repair.rar
*/
public class JavaEEbugRepair{
/*
* 官方描述：
* S2-016：https://cwiki.apache.org/confluence/display/WW/S2-016
* S2_016 bug repair
*/
private static S2_0XX s2_016 = new S2_0XX();
/*
* 修改 ognl.Ognl#parseExpression,调用 check_s2_016 方法
* public static Object parseExpression(String expression)throws OgnlException
* {
* //modify point begin
* if(JavaEEBug.check_s2_016(expression)){
* return null
* }
* //modify point end
* try {
* OgnlParser parser = new OgnlParser(new StringReader(expression));
* return parser.topLevelExpression();
* } catch (ParseException e) {
* throw new ExpressionSyntaxException(expression, e);
* } catch (TokenMgrError e) {
* throw new ExpressionSyntaxException(expression, e);
* }
* }
*/
public static boolean repair_s2_016(String expression){
return s2_016.check(expression);
}
/*
* 在servlet/struts/spring 任何一个框架的listener中调用
*/
public static void initRepair_S2_016(){
OgnlRuntime.setMethodAccessor(Runtime.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(System.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(ProcessBuilder.class,new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(OgnlRuntime.class, new NoMethodAccessor());
//io敏感操作
OgnlRuntime.setMethodAccessor(OutputStream.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(InputStream.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(File.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(DataOutput.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(DataInput.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(Reader.class, new NoMethodAccessor());
OgnlRuntime.setMethodAccessor(Writer.class, new NoMethodAccessor());
s2_016 = new S2_0XX(){
public boolean check(String expression){
String evalMethod[] = {"Runtime", "ProcessBuilder","java.io.File","new File","OutputStream","InputStream"};
String methodString = null;
methodString = expression.toLowerCase();
for (int i = 0; i < evalMethod.length; i++) {
if (methodString.indexOf(evalMethod[i].toLowerCase()) > -1) {
System.out.print("|OGNL正在执行恶意语句|" + methodString + "|看到这个消息，请联系安全工程师！！！");
return true;
}
}
return false;
}
};
}
/*
* S2-017：https://cwiki.apache.org/confluence/display/WW/S2-017
* S2_017 bug repair
*/
private static S2_0XX s2_017 = new S2_0XX();
/*
* Call by org.apache.struts2.dispatcher.mapper.DefaultActionMapper#handleSpecialParameters
* Repair Example :
* public void handleSpecialParameters(HttpServletRequest request, ActionMapping mapping)
* {
* Set uniqueParameters = new HashSet();
* Map parameterMap = request.getParameterMap();
* Iterator iterator = parameterMap.keySet().iterator();
* while (iterator.hasNext()) {
* String key = (String)iterator.next();
*
* if ((key.endsWith(".x")) || (key.endsWith(".y"))) {
* key = key.substring(0, key.length() - 2);
* }
* //modify point begin
* if (JavaEEBug.check_s2_017(key)) {
* return;
* }
* //modify point end
* if (!uniqueParameters.contains(key)) {
* ParameterAction parameterAction = (ParameterAction)this.prefixTrie.get(key);
*
* if (parameterAction != null) {
* parameterAction.execute(key, mapping);
* uniqueParameters.add(key);
* break;
* }
* }
* }
* }
*/
public static boolean repair_s2_017(String key){
return s2_017.check(key);
}
/*
* 在servlet/struts/spring 任何一个框架的listener中调用
*/
public static void initRepair_S2_017(){
s2_017 = new S2_0XX(){
public boolean check(String key){
return (key.contains("redirect:")) || (key.contains("redirectAction:")) || (key.contains("action:"));
}
};
}
}
/**
* 漏洞验证修复之基类
* 说明：
* 漏洞修复代码的实现逻辑,非侵入式设计。
* 当listener中未调用initRepair_S2_016、initRepair_S2_017进行漏洞调用初始化时,
* 保持Ognl和DefaultActionMapper修复前源码等价逻辑.
*
*/
class S2_0XX {
public boolean check(String key){
return false;
}
}
class NoMethodAccessor implements MethodAccessor {
public NoMethodAccessor() {
}
@Override
public Object callStaticMethod(Map context, Class targetClass,
String methodName, Object[] args) throws MethodFailedException {
if(targetClass!=null){
System.out.println("拦截并拒绝敏感操作: static "+targetClass.getName()+"#"+methodName);
}
throw new MethodFailedException("do not run", methodName, null);
}
@Override
public Object callMethod(Map context, Object target, String methodName,
Object[] args) throws MethodFailedException {
// TODO Auto-generated method stub
if(target!=null){
System.out.println("拦截并拒绝敏感操作:"+target.getClass().getName()+"#"+methodName);
}
throw new MethodFailedException("do not run", methodName,null);
}
}
附：org.apache.struts2.dispatcher.mapper.DefaultActionMapper.java，完整包参见struts2_S016_S017_repair.rar解压目录
重写Struts2核心包的DefaultActionMapper类。
每个版本的DefaultActionMapper类不一样，可以用反编译工具
取出org.apache.struts2.dispatcher.mapper.DefaultActionMapper.java的全部代码重写编译
修改地方handleSpecialParameters方法上的while循环体里添加：
if (JavaEEbugRepair.repair_s2_017(key)) {
return;
}
这样受攻击就会判断返回，返回的显示是一串html静态代码，漏洞解决成功!
public void handleSpecialParameters(HttpServletRequest request, ActionMapping mapping)
{
Set uniqueParameters = new HashSet();
Map parameterMap = request.getParameterMap();
Iterator iterator = parameterMap.keySet().iterator();
while (iterator.hasNext()) {
String key = (String)iterator.next();
if ((key.endsWith(".x")) || (key.endsWith(".y"))) {
key = key.substring(0, key.length() - 2);
}
if (JavaEEbugRepair.repair_s2_017(key)) {
return;
}
if (!uniqueParameters.contains(key)) {
ParameterAction parameterAction = (ParameterAction)this.prefixTrie.get(key);
if (parameterAction != null) {
parameterAction.execute(key, mapping);
uniqueParameters.add(key);
break;
}
}
}
}参考:http://blog.csdn.net/jzshmyt/article/details/9842501
http://software.intel.com/zh-cn/blogs/2013/08/08/struts2-s2-016s2-017/?utm_campaign=CSDN&utm_source=intel.csdn.net&utm_medium=Link&utm_content=others-%20Struts2
网上的多种方案：http://star.baidu.com/forum/forum.php?mod=viewthread&tid=1945