木马下载者程序
trojan-downloader.win32.agent.blyw
捕获时间
2010-1-19
危害等级
高
病毒症状
该样本是使用“visual c /c”编写的“木马下载者”程序，由微点主动防御软件自动捕获，长度为199,680字节，图标为“
”， 使用“ exe”扩展名，通过网页木马、下载器下载、等方式进行传播。
用户中毒后，会出现计算机及网络运行缓慢，出现大量未知进程等现象。
感染对象
windows 2000/windows xp/windows 2003/windows vista
传播途径
网页挂马、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"trojan-downloader.win32.agent.blyw”，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、手动删除以下文件：
x:\autorun.inf
x:\recycle.{645ff040-5081-101b-9f08-00aa002f954e}
[x为移动介质]
2、手动删除以下注册表：
hkey_local_machine\system\currentcontrolset\services\wowsu
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\360rp.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\360rpt.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\360safe.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\360safeup.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\360sd.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\360tray.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\360upp.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\arpfw.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\arswp.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\ast.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\autorun.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\autorunkiller.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\avmonitor.exe]
[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\ccenter.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\egui.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\frameworkservice.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\gfupd.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\guardfield.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\hijackthis.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\icesword.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\iparmor.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kasarp.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kav32.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kavpfw.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\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\kregex.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\krnl360svc.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kswebshield.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kvmonxp.kxp]
[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\kvwsc.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\liveupdate360.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\mmsk.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\navapsvc.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\nod32krn.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\nod32kui.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\pfw.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\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\ravservice.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\ravtask.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\ravtray.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\rfwmain.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\rfwproxy.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\rfwstub.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\rsaupd.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\rsmain.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\runiep.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\scanfrm.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\srengldr.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\trojandetector.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\trojanwall.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\trojdie.kxp]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\vpc32.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\vstskmgr.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\woptilities.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\zhudongfangyu.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\修复工具.exe]
3、手动替换以下文件：
%systemroot%\system32\appmgmts.dll
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.病毒运行后检查所在盘符是否为可移动磁盘，如果是就执行explorer.exe。
2.尝试打开管道"\\.\pipe\96dba249-e88e-4c47-98dc-e18e6e3e3e5a"，如果失败就创建"%systemdriver%\delinfo.bin"。
3.遍历进程，如果发现"ravmond.exe"和"avp.exe",就调用loadlibraryex在用户空间加载ntkrnlpa.exe，通过getproceaddress获取"ntvdmcontrol"在用户空间的地址，计算出"ntvdmcontrol"在内核空间地址，通过访问"\device\physicalmemory"，修改"ntvdmcontrol"函数前24个字节，然后调用"ntvdmcontrol"，进入ring0执行代码。
4.释放文件" %temp%\2174.dll"，修改服务appmgmt注册表项，退出当前进程。
5.如果没有发现"ravmond.exe"和"avp.exe"进程，调用sfc_os.dll#5去掉appmgmts.dll系统保护，替换appmgmts.dll，重启appmgmt服务， 退出当前进程。
6.对非windowsupdate、windows nt、windows media player、outlook express、netmeeting、msn game zone、mover maker、microsoft frontpage、messager、internet explorer、installshield installation information、complus application、common files、recycler、system volume information、documents and setting、winnt、windows文件夹中扩展名为exe、htm、html、asp、aspx和rar文件进行感染。
7.在2174.dll和appmgmts.dll中，以同样方式修改"ntvdmcontrol"进入ring0，释放驱动文件"%temp%\wowsub.sys"，创建名称为wowsub的服务，通过向"\\.\wowsub"的设备发送控制码来恢复ssdt和创建大量安全软件的映像劫持，删除安全模式相关注册表项。
8.遍历磁盘，查找可移动磁盘，创建autorun.inf和recycle.{645ff040-5081-101b-9f08-00aa002f954e}。
9.枚举局域网共享，进行弱口令猜解，将病毒自身写入共享，调用命令行at设置运行时间。
10.修改hosts文件，连接网络，下载病毒到本地执行。
病毒创建文件：
%systemroot%\windowsupdata.jpg
%systemdriver%\delinfo.bin
%temp%\wowsub.sys
x:\autorun.inf
x:\recycle.{645ff040-5081-101b-9f08-00aa002f954e}
[x为移动介质]
病毒删除文件：
%systemdriver%\delinfo.bin
%temp%\wowsub.sys
病毒替换文件：
%systemroot%\system32\appmgmts.dll
病毒修改注册表：
hkey_local_machine\system\currentcontrolset\services\appmgmt\parameters
病毒创建注册表：
hkey_local_machine\system\currentcontrolset\services\wowsu
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\360rp.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\360rpt.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\360safe.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\360safeup.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\360sd.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\360tray.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\360upp.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\arpfw.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\arswp.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\ast.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\autorun.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\autorunkiller.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\avmonitor.exe]
[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\ccenter.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\egui.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\frameworkservice.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\gfupd.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\guardfield.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\hijackthis.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\icesword.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\iparmor.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kasarp.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kav32.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kavpfw.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\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\kregex.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\krnl360svc.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kswebshield.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\kvmonxp.kxp]
[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\kvwsc.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\liveupdate360.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\mmsk.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\navapsvc.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\nod32krn.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\nod32kui.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\pfw.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\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\ravservice.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\ravtask.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\ravtray.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\rfwmain.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\rfwproxy.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\rfwstub.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\rsaupd.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\rsmain.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\runiep.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\scanfrm.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\srengldr.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\trojandetector.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\trojanwall.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\trojdie.kxp]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\vpc32.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\vstskmgr.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\woptilities.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\zhudongfangyu.exe]
[hkey_local_machine\software\microsoft\windows nt\currentversion\image file execution options\修复工具.exe]
病毒删除注册表：
hkey_local_machine\system\currentcontrolset\control\safeboot\minimal
hkey_local_machine\system\currentcontrolset\control\safeboot\network |
