Trojan.Win32.FlyStudio_c8c25605dc

Dynamic Analysis

Payload

Behaviour	Description
EmailWorm	Worm can send e-mails.

Process activity

The Trojan creates the following process(es):No processes have been created.The Trojan injects its code into the following process(es):

%original file name%.exe:404

File activity

The process %original file name%.exe:404 makes changes in the file system.

The Trojan creates and/or writes to the following file(s):

C:\SkinH_EL.dll (88 bytes)

Registry activity

The process %original file name%.exe:404 makes changes in the system registry.

The Trojan creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths]
"Directory" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path4]
"CacheLimit" = "65452"
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache4"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Connections]
"SavedLegacySettings" = "3C 00 00 00 19 00 00 00 01 00 00 00 00 00 00 00"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"AppData" = "%Documents and Settings%\%current user%\Application Data"

"Cookies" = "%Documents and Settings%\%current user%\Cookies"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache2"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Common AppData" = "%Documents and Settings%\All Users\Application Data"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"Cache" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files"

[HKLM\System\CurrentControlSet\Hardware Profiles\0001\Software\Microsoft\windows\CurrentVersion\Internet Settings]
"ProxyEnable" = "0"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1]
"CacheLimit" = "65452"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path2]
"CacheLimit" = "65452"

[HKLM\SOFTWARE\Microsoft\Cryptography\RNG]
"Seed" = "CC 7D EE 4C 3F E6 11 B0 41 DA 87 79 24 D1 62 D8"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path1]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache1"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3]
"CacheLimit" = "65452"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"MigrateProxy" = "1"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders]
"History" = "%Documents and Settings%\%current user%\Local Settings\History"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths\path3]
"CachePath" = "%Documents and Settings%\%current user%\Local Settings\Temporary Internet Files\Content.IE5\Cache3"

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\Cache\Paths]
"Paths" = "4"

[HKCU\Software\Microsoft\Multimedia\DrawDib]
"vga.drv 1276x846x32(BGR 0)" = "31,31,31,31"

The Trojan modifies IE settings for security zones to map all local web-nodes with no dots which do not refer to any zone to the Intranet Zone:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"UNCAsIntranet" = "1"

To automatically run itself each time Windows is booted, the Trojan adds the following link to its file to the system registry autorun key:

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
"С°Ë°æ±¾¸üÐÂ.exe" = "c:\%original file name%.exe"

The Trojan modifies IE settings for security zones to map all web-nodes that bypassing the proxy to the Intranet Zone:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"ProxyBypass" = "1"

Proxy settings are disabled:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"ProxyEnable" = "0"

The Trojan modifies IE settings for security zones to map all urls to the Intranet Zone:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"IntranetName" = "1"

The Trojan deletes the following value(s) in system registry:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings]
"AutoConfigURL"
"ProxyServer"
"ProxyOverride"

Dropped PE files

MD5	File path
147127382e001f495d1842ee7a9e7912	c:\SkinH_EL.dll

HOSTS file anomalies

No changes have been detected.

Rootkit activity

No anomalies have been detected.

Propagation

Removals

Remove it with Ad-Aware

1. Click (here) to download and install Ad-Aware Free Antivirus.
2. Update the definition files.
3. Run a full scan of your computer.

Manual removal*

1. Terminate malicious process(es) (How to End a Process With the Task Manager):No processes have been created.
2. Delete the original Trojan file.
   
3. Delete or disinfect the following files created/modified by the Trojan:

   C:\SkinH_EL.dll (88 bytes)

4. Delete the following value(s) in the autorun key (How to Work with System Registry):

   [HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
   "С°Ë°æ±¾¸üÐÂ.exe" = "c:\%original file name%.exe"

5. Clean the Temporary Internet Files folder, which may contain infected files (How to clean Temporary Internet Files folder).
   
6. Reboot the computer.
   

*Manual removal may cause unexpected system behaviour and should be performed at your own risk.

Static Analysis

VersionInfo

Company Name:
Product Name: ?????
Product Version: 1.0.0.0
Legal Copyright: ?????? ????????
Legal Trademarks:
Original Filename:
Internal Name:
File Version: 1.0.0.0
File Description: ?????
Comments: ??????????(http://www.eyuyan.com)
Language: English (United States)

Company Name: Product Name: ?????Product Version: 1.0.0.0Legal Copyright: ?????? ????????Legal Trademarks: Original Filename: Internal Name: File Version: 1.0.0.0File Description: ?????Comments: ??????????(http://www.eyuyan.com)Language: English (United States)

PE Sections

Name	Virtual Address	Virtual Size	Raw Size	Entropy	Section MD5
.text	4096	459798	462848	4.53827	80b3e15cff32ebcbfd7314971aa55935
.rdata	466944	3178462	3178496	5.34907	c99825f99d0ebc088335dcd82b02e44c
.data	3645440	266698	61440	3.38615	01e938f1f23778bc5c232c1b3a20d016
.rsrc	3915776	22336	24576	3.31557	130774f231929b97276d75d6c1533080

Dropped from:

Downloaded by:

Similar by SSDeep:

Similar by Lavasoft Polymorphic Checker:

Network Activity

URLs

URL	IP
hxxp://bcs.duapp.com/xiaoba/......../config.xml	123.125.114.82

IDS verdicts (Suricata alerts: Emerging Threats ET ruleset)

Traffic

GET /xiaoba/......../config.xml HTTP/1.1

User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)

Accept: */*

Host: bcs.duapp.com

Cache-Control: no-cache

HTTP/1.1 200 OK

Access-Control-Allow-Origin: *

Access-Control-Allow-Methods: GET, PUT, POST, DELETE, OPTIONS, HEAD

Access-Control-Allow-Headers: Origin, Content-Type, Accept, Content-Length

Accept-Ranges: bytes

Last-Modified: Thu, 08 May 2014 14:51:28 GMT

Expires: Sat, 24 May 2014 15:17:46 GMT

x-bs-version: 99843B68E4889158BA094511C49158BD

ETag: 67bd0f15aeb038a83139fee5c7c86ea6

Content-Type: text/xml

x-bs-request-id: MTAuMjMuMzcuMjk6ODA4MDoxOTQ5NzA0ODc4OjIxL01heS8yMDE0IDIzOjE3OjQ2IA==

Cache-Control: no-cache

x-bs-meta-crc32: 2472933773

Content-MD5: 67bd0f15aeb038a83139fee5c7c86ea6

x-bs-client-ip: MTkzLjEzOC4yNDQuMjMx

Content-Length: 467

Date: Wed, 21 May 2014 15:17:46 GMT

Server: BaiduBS

<?xml version="1.0" encoding="GB2312"?>..<........>..<........ ......="1.1" ........="hXXp://bcs.duapp.com/xiaoba/......../.........exe" ......="E.............exe" ........="C:\........" ........="....................2.1....................#hhf1.....................bug.#hhf2.......................BUG.#hhf3.......BUG........#hhf4...........................................#hhf5...........ISO2009-2020.............................................."/>..</........>..HTTP/1.1 200 OK..Access-Control-Allow-Origin: *..Access-Control-Allow-Methods: GET, PUT, POST, DELETE, OPTIONS, HEAD..Access-Control-Allow-Headers: Origin, Content-Type, Accept, Content-Length..Accept-Ranges: bytes..Last-Modified: Thu, 08 May 2014 14:51:28 GMT..Expires: Sat, 24 May 2014 15:17:46 GMT..x-bs-version: 99843B68E4889158BA094511C49158BD..ETag: 67bd0f15aeb038a83139fee5c7c86ea6..Content-Type: text/xml..x-bs-request-id: MTAuMjMuMzcuMjk6ODA4MDoxOTQ5NzA0ODc4OjIxL01heS8yMDE0IDIzOjE3OjQ2IA==..Cache-Control: no-cache..x-bs-meta-crc32: 2472933773..Content-MD5: 67bd0f15aeb038a83139fee5c7c86ea6..x-bs-client-ip: MTkzLjEzOC4yNDQuMjMx..Content-Length: 467..Date: Wed, 21 May 2014 15:17:46 GMT..Server: BaiduBS..<?xml version="1.0" encoding="GB2312"?>..<........>..<........ ......="1.1" ........="hXXp://bcs.duapp.com/xiaoba/......../.........exe" ......="E.............exe" ........="C:\........" ........="....................2.1....................#hhf1.....................bug.#hhf2.......................BUG.#hhf3.......BUG

<<

<<< skipped >>>

Map

The Trojan connects to the servers at the folowing location(s):

Strings from Dumps

%original file name%.exe_404:

.text

.text

`.rdata

`.rdata

@.data

@.data

.rsrc

.rsrc

t$(SSh

t$(SSh

~%UVW

~%UVW

u$SShe

u$SShe

SkinH_EL.dll

SkinH_EL.dll

SOFTWARE\Microsoft\Windows\CurrentVersion\Run\

SOFTWARE\Microsoft\Windows\CurrentVersion\Run\

%s;7*

%s;7*

0%x@w

0%x@w

%C^L:

%C^L:

%s T5

%s T5

]E4%F(

]E4%F(

.Funr

.Funr

k%UPp

k%UPp

fg.VG

fg.VG

%C',@

%C',@

>Ùd

>Ùd

0'.Ll

0'.Ll

[I(3/#N0.bd

[I(3/#N0.bd

j"%u=w

j"%u=w

q%Xn`

q%Xn`

@|H.NI

@|H.NI

.wdd!

.wdd!

S|%u4

S|%u4

*.Ea]S

*.Ea]S

Q.CGo

Q.CGo

fTpe

fTpe

.LLbX

.LLbX

-.Mdl

-.Mdl

\-A}=3K

\-A}=3K

Y:.akpS

Y:.akpS

$.Zcqn

$.Zcqn

u.Jck~

u.Jck~

zx/%FN[

zx/%FN[

ce_%D

ce_%D

%C@0H

%C@0H

%s=\RI

%s=\RI

}j%c%Y)

}j%c%Y)

Rx.GR

Rx.GR

4o#.dM

4o#.dM

IeS`%C

IeS`%C

[n 4\.UY

[n 4\.UY

,4.qO,

,4.qO,

gQ'.Io

gQ'.Io

%cLur?

%cLur?

s%DHB

s%DHB

]I%%X

]I%%X

5r.US

5r.US

:mD].tB

:mD].tB

f%fUZ

f%fUZ

.fOuV12

.fOuV12

*_.dC

*_.dC

&-N}<</pre><pre>({?.cQm</pre><pre>.Cqx~c</pre><pre>.`.Qw</pre><pre>**.dU</pre><pre>!n]%x</pre><pre>%X,Cr</pre><pre>&.PFy{xh</pre><pre>.um ZZE7L</pre><pre>/^p%u$</pre><pre>I.NoQY</pre><pre>zu.ew</pre><pre>D/.nT</pre><pre>q.7.qE</pre><pre>W>^T%S</pre><pre>%XiR^</pre><pre>1%SqlnD</pre><pre>U[5%u</pre><pre>.OW74</pre><pre>"E.jV</pre><pre>c T.Om</pre><pre>*U%XOd</pre><pre>D%FW@</pre><pre>.gM>$slt</pre><pre>B.iR%</pre><pre>vv#%sY7x</pre><pre>.TY3F</pre><pre>kEY94</pre><pre>.nyBK</pre><pre>wN%U/</pre><pre>4.Ky%t</pre><pre>.h.fO</pre><pre>.TK$N</pre><pre>%dRB:W</pre><pre>[I9%f</pre><pre>8o%sx</pre><pre>.WE= T!N</pre><pre>#?%s(C(</pre><pre>Rd.hYp</pre><pre>.TX=6</pre><pre>,%x)E</pre><pre>R%X4C (</pre><pre>$7.Gs</pre><pre>d,.bw p</pre><pre>o .Kb</pre><pre>KOz-%c Rd</pre><pre>zkey0</pre><pre>=.Lw/Ch</pre><pre>!c%SGd</pre><pre>A.YA'</pre><pre>`.yV8</pre><pre>.qL8d0{</pre><pre>m>[So;.yd] </pre><pre>_ÎW,</pre><pre>%UZtQ</pre><pre>.Fu:#</pre><pre>SShXuy@</pre><pre>f.kz"</pre><pre>@o.Ns</pre><pre>i.IK(</pre><pre>9rBÀ</pre><pre>.nm[&</pre><pre>.DDU0</pre><pre>%f$8C</pre><pre>\SkinH_EL.dll</pre><pre>C$%cmb</pre><pre>.ppM|</pre><pre> aZ.mO</pre><pre>%-^</pre><pre>.hk;~</pre><pre>KERNEL32.DLL</pre><pre>COMCTL32.dll</pre><pre>GDI32.dll</pre><pre>MSIMG32.dll</pre><pre>MSVCRT.dll</pre><pre>MSVFW32.dll</pre><pre>USER32.dll</pre><pre>http://bcs.duapp.com/xiaoba/</pre><pre>/config.xml</pre><pre>|$D.tm</pre><pre>619953407</pre><pre>anonymous@123.com</pre><pre>.exe|.rar|.zip|.gif|.jpg|.mp3|.rm</pre><pre>Y@SkinH_EL.dll</pre><pre>?456789:;<=</pre><pre>!"#$%&'()* ,-./0123</pre><pre>F%*.*f</pre><pre>CNotSupportedException</pre><pre>commctrl_DragListMsg</pre><pre>Afx:%x:%x:%x:%x:%x</pre><pre>Afx:%x:%x</pre><pre>COMCTL32.DLL</pre><pre>CCmdTarget</pre><pre>__MSVCRT_HEAP_SELECT</pre><pre>user32.dll</pre><pre>iphlpapi.dll</pre><pre>SHLWAPI.dll</pre><pre>MPR.dll</pre><pre>WINMM.dll</pre><pre>WS2_32.dll</pre><pre>VERSION.dll</pre><pre>RASAPI32.dll</pre><pre>GetProcessHeap</pre><pre>WinExec</pre><pre>KERNEL32.dll</pre><pre>GetKeyState</pre><pre>GetViewportOrgEx</pre><pre>WINSPOOL.DRV</pre><pre>RegCloseKey</pre><pre>RegOpenKeyExA</pre><pre>RegCreateKeyExA</pre><pre>ADVAPI32.dll</pre><pre>ShellExecuteA</pre><pre>SHELL32.dll</pre><pre>ole32.dll</pre><pre>OLEAUT32.dll</pre><pre>WININET.dll</pre><pre>GetCPInfo</pre><pre>CreateDialogIndirectParamA</pre><pre>UnhookWindowsHookEx</pre><pre>SetWindowsHookExA</pre><pre>SetViewportOrgEx</pre><pre>OffsetViewportOrgEx</pre><pre>SetViewportExtEx</pre><pre>ScaleViewportExtEx</pre><pre>GetViewportExtEx</pre><pre>comdlg32.dll</pre><pre>.PAVCException@@</pre><pre>.PAVCNotSupportedException@@</pre><pre>.PAVCFileException@@</pre><pre>(*.prn)|*.prn|</pre><pre>(*.*)|*.*||</pre><pre>Shell32.dll</pre><pre>Mpr.dll</pre><pre>Advapi32.dll</pre><pre>User32.dll</pre><pre>Gdi32.dll</pre><pre>Kernel32.dll</pre><pre>(&07-034/)7 '</pre><pre>?? / %d]</pre><pre>%d / %d]</pre><pre>: %d]</pre><pre>(*.WAV;*.MID)|*.WAV;*.MID|WAV</pre><pre>(*.WAV)|*.WAV|MIDI</pre><pre>(*.MID)|*.MID|</pre><pre>(*.txt)|*.txt|</pre><pre>(*.JPG;*.BMP;*.GIF;*.ICO;*.CUR)|*.JPG;*.BMP;*.GIF;*.ICO;*.CUR|JPG</pre><pre>(*.JPG)|*.JPG|BMP</pre><pre>(*.BMP)|*.BMP|GIF</pre><pre>(*.GIF)|*.GIF|</pre><pre>(*.ICO)|*.ICO|</pre><pre>(*.CUR)|*.CUR|</pre><pre>%s:%d</pre><pre>windows</pre><pre>out.prn</pre><pre>%d.%d</pre><pre>%d / %d</pre><pre>%d/%d</pre><pre>Bogus message code %d</pre><pre>(%d-%d):</pre><pre>%ld%c</pre><pre>%s <%s></pre><pre>Reply-To: %s</pre><pre>From: %s</pre><pre>To: %s</pre><pre>Subject: %s</pre><pre>Date: %s</pre><pre>Cc: %s</pre><pre>%a, %d %b %Y %H:%M:%S</pre><pre>SMTP</pre><pre>[%s:%d]</pre><pre>Range: bytes=%s-</pre><pre>[%s:%d]</pre><pre>PASS %s</pre><pre>PASS ******</pre><pre>USER %s</pre><pre>E:\dev\e\static_link\static_libs\source\downlib\mystrlib.cpp</pre><pre>SIZE %s</pre><pre>PORT</pre><pre>User-Agent: %s</pre><pre>Mozilla/4.0 (compatible; MSIE 5.00; Windows 98)</pre><pre>Referer: %s</pre><pre>Host: %s</pre><pre>GET %s HTTP/1.1</pre><pre>HTTP/1.0</pre><pre>HTTP/1.1</pre><pre>http://</pre><pre>Cookie: %s</pre><pre>%d, %s</pre><pre>\\192.168.0.129\TCP\1037</pre><pre>NSPlayer/9.0.0.2980; {%s}; Host: %s</pre><pre>rmff_fix_header: assuming data.size=%i</pre><pre>rmff_fix_header: assuming data.num_packets=%i</pre><pre>rmff_fix_header: assuming prop.num_packets=%i</pre><pre>rmff_fix_header: setting prop.data_offset from %i to %i</pre><pre>rmff_fix_header: correcting prop.num_streams from %i to %i</pre><pre>rmff_fix_header: correcting prop.size from %i to %i</pre><pre>%s %s %s</pre><pre>Session: %s</pre><pre>Cseq: %u</pre><pre>%*s %s</pre><pre>%*s %u</pre><pre>CSeq: %u</pre><pre>rtsp://%s:%i</pre><pre>rtsp://%s:%i/%s</pre><pre>ClientID: Linux_2.4_6.0.9.1235_play32_RN01_EN_586</pre><pre>GUID: 00000000-0000-0000-0000-000000000000</pre><pre>[%s:%d]</pre><pre>User-Agent: RealMedia Player Version 6.0.9.1235 (linux-2.0-libc6-i386-gcc2.95)</pre><pre>Range: npt=%s-</pre><pre>%s/streamid=1</pre><pre>%s/streamid=0</pre><pre>Transport: x-pn-tng/tcp;mode=play,rtp/avp/tcp;unicast;mode=play</pre><pre>If-Match: %s</pre><pre>RealChallenge2: %s, sd=%s</pre><pre>Title: %s</pre><pre>Copyright: %s</pre><pre>Author: %s</pre><pre>real: Content-length for description too big (> %uMB)!</pre><pre>Require: com.real.retain-entity-for-setup</pre><pre>SupportsMaximumASMBandwidth: 1</pre><pre>Bandwidth: %u</pre><pre>Challenge1: %s</pre><pre>hash output: %x %x %x %x</pre><pre>hash input: %x %x %x %x</pre><pre>stream=%u;rule=%u,</pre><pre>Illegal character '%c' in input.</pre><pre>.PAVCObject@@</pre><pre>.PAVCSimpleException@@</pre><pre>.PAVCMemoryException@@</pre><pre>.?AVCNotSupportedException@@</pre><pre>.PAVCResourceException@@</pre><pre>.PAVCUserException@@</pre><pre>.?AVCCmdTarget@@</pre><pre>.?AVCCmdUI@@</pre><pre>.?AVCTestCmdUI@@</pre><pre>.PAVCArchiveException@@</pre><pre>zcÁ</pre><pre>#include "l.chs\afxres.rc" // Standard components</pre><pre>http://www.56.com/w56/play_album-aid-12119442_vid-MTAxMzAzNTA2.html</pre><pre>RegCreateKeyA</pre><pre>WSOCK32.dll</pre><pre>HttpQueryInfoA</pre><pre>HttpSendRequestA</pre><pre>HttpOpenRequestA</pre><pre>InternetCrackUrlA</pre><pre>InternetCanonicalizeUrlA</pre><pre>Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)</pre><pre>www.dywt.com.cn</pre><pre>s.duapp.com/xiaoba/</pre><pre>="http://bcs.duapp.com/xiaoba/</pre><pre>.exe"</pre><pre>c:\%original file name%.exe</pre><pre>1, 0, 6, 6</pre><pre>(*.*)</pre><pre>1.0.0.0</pre><pre>(http://www.eyuyan.com)</pre><b>%original file name%.exe_404_rwx_10001000_00039000:</b><pre>L$(h%f</pre><pre>SSh0j</pre><pre>msctls_hotkey32</pre><pre>TVCLHotKey</pre><pre>THotKey</pre><pre>\skinh.she</pre><pre>}uo,x6l5k%x-l h</pre><pre>9p%s m)t4`#b</pre><pre>e"m?c&y1`Ð<</pre><pre>SetViewportOrgEx</pre><pre>SetViewportExtEx</pre><pre>SetWindowsHookExA</pre><pre>UnhookWindowsHookEx</pre><pre>EnumThreadWindows</pre><pre>EnumChildWindows</pre><pre>`c%US.4/</pre><pre>!#$<#$#=</pre><pre>.text</pre><pre>`.rdata</pre><pre>@.data</pre><pre>.rsrc</pre><pre>@.UPX0</pre><pre>`.UPX1</pre><pre>`.reloc</pre></pre>