木马下载器
trojan-downloader.win32.geral.a
捕获时间
2010-4-28
危害等级
中
病毒症状
该样本是使用“c ”编写的木马下载器，由微点主动防御软件自动捕获，采用“upack”加壳方式，企图躲避特征码扫描，加壳后长度为“34,311”，图标为“
”，病毒扩展名为“exe”，主要通过“文件捆绑”、“下载器下载”、“网页挂马”等方式传播，病毒主要目的是下载安装病毒木马。
用户中毒后，会出现本地磁盘无法双击打开，杀软无故退出，系统运行缓慢，出现大量未知进程，系统无故报错等现象。
感染对象
windows 2000/windows xp/windows 2003/windows vista/ windows 7
传染途径
网页木马、文件捆绑、下载器下载
防范措施
已安装使用微点主动防御软件的用户，无须任何设置，微点主动防御将自动保护您的系统免受该病毒的入侵和破坏。无论您是否已经升级到最新版本，微点主动防御都能够有效清除该病毒。如果您没有将微点主动防御软件升级到最新版，微点主动防御软件在发现该病毒后将报警提示您发现“未知木马“，请直接选择删除处理（如图1）；
图1 微点主动防御软件自动捕获未知病毒（未升级）
如果您已经将微点主动防御软件升级到最新版本，微点将报警提示您发现木马"trojan-downloader.win32.geral.a”，请直接选择删除（如图2）。
图2 微点主动防御软件升级后截获已知病毒
未安装微点主动防御软件的手动解决办法：
1.结束以下进程extext6401515t.exe。
2.删除注册表hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options下的映像劫持项
3.用正常的hosts文件替换%systemroot%\system32\drivers\etc\hosts
4.手动删除以下文件：
%systemroot%\extext6401515t.exe
%systemroot%\system32\scvhost.exe
变量声明：
%systemdriver% 系统所在分区，通常为“c:\”
%systemroot% windodws所在目录，通常为“c:\windows”
%documents and settings% 用户文档目录，通常为“c:\documents and settings”
%temp% 临时文件夹，通常为“c:\documents and settings\当前用户名称\local settings\temp”
%programfiles% 系统程序默认安装目录，通常为：“c:\programfiles”
病毒分析：
(1)病毒调用命令行，禁用eset服务项并结束eset进程：
"cmd /c sc config ekrn start= disabled"
"cmd.exe /c taskkill.exe /im ekrn.exe /f"
"cmd.exe /c taskkill.exe /im egui.exe /f"
(2)病毒获取系统路径，创建文件%systemroot%\tete3032906t.dll，调用rundll32.exe以testall参数执行tete3032906t.dll(随机命名)。待执行完毕后删除tete3032906t.dll
(3)病毒获取系统路径，创建文件%systemroot%\extext6401515t.exe(随机命名)并执行extext6401515t.exe
(4)提升自身权限，创建驱动%systemroot%\system32\drivers\pcidump.sys，为该驱动创建名称为pcidump的服务项并开启服务项。服务开启后向驱动发送消息，注入userinit.exe。完成后删除该服务项和驱动文件。
(5)病毒将自身重命名复制为%systemroot%\system32\scvhost.exe
(6)tete3032906t.dll提升自身权限，释放驱动文件aec.sys和asyncmac.sys至%systemroot%\system32\drivers\目录下，并为其分别建立名称为aec和asyncmac的服务项。关闭系统中存在的安全软件驱动。枚举所有常见安全软件的服务项和进程名。若发现，则关闭该安全软件服务项、结束其进程并删除相应程序，同时建立该安全软件的映像劫持，使其不能启动。被劫持的映像有："avp.exe"、"safeboxtray.exe"、"360safebox.exe"、"antiarp.exe"、"ekrn.exe"、"rsagent.exe"、"mfeann.exe"、"egui.exe"、"ravmon.exe"、"ravmond.exe"、"ravtask.exe"、"ccenter.exe"、"ravstub.exe"、"rstray.exe"、"scanfrm.exe"、"rav.exe"、"agentsvr.exe"、"qqdoctor.exe"、"mcproxy.exe"、"mcshield.exe"、"rsnetsvr.exe"、"naprdmgr.exe"、"mpfsrv.exe"、"mpsvc.exe"、"mpsvc1.exe"、"kissvc.exe"、"kpfwsvc.exe"、"kmailmon.exe"、"kavstart.exe"、"engineserver.exe"、"kpfw32.exe"、"kvsrvxp.exe"、"ccsetmgr.exe"、"ccevtmgr.exe"、"defwatch.exe"、"rtvscan.exe"、"ccapp.exe"、"vptray.exe"、"mcupdmgr.exe"、"mfevtps.exe"、"mcsysmon.exe"、"mcmscsvc.exe"、"mcnasvc.exe"、"mcagent.exe"、"vstskmgr.exe"、"frameworkservice.exe"、"mcshell.exe"、"mcinsupd.exe"、"bdagent.exe"、"livesrv.exe"、"vsserv.exe"、"xcommsvr.exe"、"ccsvchst.exe"、"shstat.exe"、"mctray.exe"、"udaterui.exe"、"kavstart.exe"、"uplive.exe"、"kwatch.exe"、"qqdoctorrt.exep"、"drupdate.exe"、"rfwsrv.exe"、"regguide.exe"、"mpsvc2.exe"、"mpmon.exe"、"liveupdate360.exe"。获取ssdt地址，恢复ssdt。成功后删除服务项和驱动文件。
(7)extext6401515t.exe提升自身权限，关闭windows防火墙的alg服务项和安全中心的wscsvc服务项。并通过注册表将病毒创建的文件%systemroot%\system32\scvhost.exe加载为开机启动项。
hkey_local_machine\software\microsoft\windows\currentversion\run
名称：rstray
数据：c:\windows\system32\scvhost.exe
(8)病毒访问网络，下载文件替换%systemroot%\system32\drivers\etc\hosts文件。打开netbios服务，从指定地址下载大量病毒木马到本地运行。
病毒创建文件：
%systemroot%\tete3032906t.dll
%systemroot%\system32\drivers\aec.sys
%systemroot%\system32\drivers\asyncmac.sys
%systemroot%\extext6401515t.exe
%systemroot%\system32\drivers\pcidump.sys
%systemroot%\system32\scvhost.exe
%systemroot%\system32\drivers\etc\hosts
病毒创建进程：
extext6401515t.exe
病毒创建注册表：
hkey_local_machine\system\currentcontrolset\services\pcidump
hkey_local_machine\system\currentcontrolset\services\aec
hkey_local_machine\system\currentcontrolset\services\asyncmac
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\avp.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\safeboxtray.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\360safebox.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\antiarp.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\ekrn.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\rsagent.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mfeann.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\egui.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\ravmon.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\ravmond.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\ravtask.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\ccenter.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\ravstub.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\rstray.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\scanfrm.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\rav.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\agentsvr.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\qqdoctor.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mcproxy.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mcshield.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\rsnetsvr.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\naprdmgr.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mpfsrv.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mpsvc.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mpsvc1.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kissvc.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kpfwsvc.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kmailmon.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kavstart.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\engineserver.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kpfw32.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kvsrvxp.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\ccsetmgr.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\ccevtmgr.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\defwatch.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\rtvscan.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\ccapp.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\vptray.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mcupdmgr.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mfevtps.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mcsysmon.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mcmscsvc.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mcnasvc.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mcagent.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\vstskmgr.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\frameworkservice.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mcshell.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mcinsupd.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\bdagent.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\livesrv.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\vsserv.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\xcommsvr.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\ccsvchst.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\shstat.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mctray.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\udaterui.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kavstart.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\uplive.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kwatch.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\qqdoctorrtp.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\drupdate.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\rfwsrv.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\regguide.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mpsvc2.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\mpmon.exe
hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\liveupdate360.exe
hkey_local_machine\software\microsoft\windows\currentversion\run
名称：rstray
数据：c:\windows\system32\scvhost.exe
病毒删除文件：
%systemroot%\tete3032906t.dll
%systemroot%\system32\drivers\pcidump.sys
病毒删除注册表：
hkey_local_machine\system\currentcontrolset\services\pcidump
hkey_local_machine\system\currentcontrolset\services\aec
hkey_local_machine\system\currentcontrolset\services\asyncmac
病毒访问网络：
http://qweqwe.x***ns.com:18364/host.pcx
http://ht8.we***od.net:94/18/tj.asp
http://qweqwe.x***ns.com:18364/dns.pcx |
