Microsoft Works 7 WkImgSrv.dll ActiveX控件远程代码执行漏洞

BUGTRAQ ID: 28820 Microsoft Works是微软在早期所发布的文件处理程序。 Microsoft Works所带的ActiveX控件实现上存在漏洞，远程攻击者可能利用此漏洞控制用户系统。 Microsoft Works所提供的wkimgsrv.dll库没有安全地调用WKsPictureInterface方式： 00D473BD PUSH EBP ; Begin of Set WksPictureInterface method 00D473BE MOV EBP,ESP 00D473C0 SUB ESP,1C 00D473C3 MOV EAX,DWORD PTR SS:[EBP+C] ; Move paramater to EAX 00D473C6 PUSH ESI 00D473C7 TEST EAX,EAX ; Checking whether EAX is NULL 00D473C9 JNZ SHORT wkimgsrv.00D473D5 ; OK,if it is not null continue 00D473CB MOV EAX,80004005 ; 00D473D0 JMP wkimgsrv.00D47456 ;No,it's is NULL,exit method 00D473D5 ==&gt; MOV ESI,DWORD PTR SS:[EBP+8] ; Do some other stuffs, we don't care 00D473D8 LEA EDX,DWORD PTR SS:[EBP-1C] ; 00D473DB PUSH EDX 00D473DC PUSH EAX 00D473DD MOV DWORD PTR DS:[ESI+2A0],EAX ; ============= 00D473E3 ==&gt; MOV ECX,DWORD PTR DS:[EAX] ; Here is the problem,the data stored by EAX is referenced and moved into ECX 00D473E5 CALL DWORD PTR DS:[ECX+30] ;Next the address in some struct pointed by ECX is called 如果能够在内存中创建第一个DWORD指向其本身且0x30偏移处的DWORD指向shellcode的结构，则当用户在访问恶意网页时就可能触发无效的内存访问，导致拒绝服务或执行任意指令。 Microsoft Works 7 Microsoft --------- 目前厂商还没有提供补丁或者升级程序，我们建议使用此软件的用户随时关注厂商的主页以获取最新版本： <a href=http://www.microsoft.com/technet/security/ target=_blank>http://www.microsoft.com/technet/security/</a>