Gen.Variant.MSIL.Mensa.11_8f4f2c8628

by malwarelabrobot on August 31st, 2017 in Malware Descriptions.

Trojan.MSIL.Crypt.ecwt (Kaspersky), Gen:Variant.MSIL.Mensa.11 (B) (Emsisoft), Gen:Variant.MSIL.Mensa.11 (AdAware)
Behaviour: Trojan


The description has been automatically generated by Lavasoft Malware Analysis System and it may contain incomplete or inaccurate information.

Requires JavaScript enabled!

Summary
Dynamic Analysis
Static Analysis
Network Activity
Map
Strings from Dumps
Removals

MD5: 8f4f2c8628ecf10290844bcae4c745dd
SHA1: 389fd18a5ed7c7964265355cb8ca4435f675a2ba
SHA256: 36359cede7000a7421b2888fc3a34addf583b25f296d3b6faab5bf13e1f3a438
SSDeep: 24576:k8Rn2/2kNSL77s/25gXq4wv9SAXSIxwkrPRdGu6l2OzsVc:kA2/iL7iCsPwvgA1xbPRdGu6l2Oh
Size: 1196032 bytes
File type: EXE
Platform: WIN32
Entropy: Packed
PEID: MicrosoftVisualC, NETexecutable, UPolyXv05_v6
Company: Nego
Created at: 2017-07-10 15:31:07
Analyzed on: Windows7 SP1 32-bit


Summary:

Trojan. A program that appears to do one thing but actually does another (a.k.a. Trojan Horse).

Payload

No specific payload has been found.

Process activity

The Trojan creates the following process(es):

vbc.exe:4028
%original file name%.exe:3400

The Trojan injects its code into the following process(es):

Windows Update.exe:1588

Mutexes

The following mutexes were created/opened:
No objects were found.

File activity

The process Windows Update.exe:1588 makes changes in the file system.
The Trojan creates and/or writes to the following file(s):

C:\Users\"%CurrentUserName%"\AppData\Roaming\pid.txt (4 bytes)
C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Tar24D1.tmp (2712 bytes)
C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Tar3B40.tmp (2712 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\WindowsUpdate.exe (7726 bytes)
C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Cab24BF.tmp (51 bytes)
C:\Users\"%CurrentUserName%"\AppData\LocalLow\Microsoft\CryptnetUrlCache\Content\94308059B57B3142E455B38A6EB92015 (52 bytes)
C:\Windows\System32\drivers\etc\hosts (59 bytes)
C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Cab3B3F.tmp (52 bytes)
C:\Users\"%CurrentUserName%"\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015 (1720 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\pidloc.txt (47 bytes)
C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Cab24D0.tmp (51 bytes)
C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Tar24C0.tmp (2712 bytes)

The Trojan deletes the following file(s):

C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\OF9L3DR3.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\983WD333.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\YJCP8HIK.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\P2Z07O4S.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Cab3B3F.tmp (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\GF0JZXVN.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\00CZ9B9Z.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\QVWF9XLH.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\Z40SB5AS.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\59FYE1S2.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\4CWVLDFS.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\K3H6JGON.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\SHMEGTHE.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\379IMDJA.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Tar3B40.tmp (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\G6NPTRAV.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\HGQPYGV7.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Local\Temp\holdermail.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\A5VV6NGJ.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\O761920L.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\SK6RC4AQ.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\7ZFPBM01.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\PMGXNABP.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\AJQLWW1A.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\K4EMAOY7.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Tar24C0.tmp (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\CZKDRHGB.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Mozilla\Firefox\Profiles\5a2ce8gs.default\cookies.sqlite (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\9UFT3VMU.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\FBUBDDF0.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\8WNTYFZE.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\winlogon.exe (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\FDGZES7U.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\SN1VAMHK.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\ETGRPT21.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\VPSNR0J4.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Tar24D1.tmp (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\8Q2KNK5G.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\NWCBOWT9.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\1I56O6EZ.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\PFR2GFQJ.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\GB74HSLE.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\KUZ61ORW.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\KE9BMB37.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Cab24BF.tmp (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\LXL295FY.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\KJGZP41Y.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\XJJJSX58.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\KCULDY7L.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\03Z3OHNC.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\AW5IGQT7.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\KK0IK9EV.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\0VR58838.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Local\Temp\holderwb.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\IAU75TW2.txt (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Cab24D0.tmp (0 bytes)
C:\Users\"%CurrentUserName%"\AppData\Roaming\Microsoft\Windows\Cookies\OLCWAOT0.txt (0 bytes)

The process vbc.exe:4028 makes changes in the file system.
The Trojan creates and/or writes to the following file(s):

C:\Users\"%CurrentUserName%"\AppData\Local\Temp\holderwb.txt (2 bytes)

The process %original file name%.exe:3400 makes changes in the file system.
The Trojan creates and/or writes to the following file(s):

C:\Users\"%CurrentUserName%"\AppData\Roaming\winlogon.exe (7775 bytes)

Registry activity

The process Windows Update.exe:1588 makes changes in the system registry.
The Trojan creates and/or sets the following values in system registry:

[HKLM\SOFTWARE\Microsoft\Tracing\Windows Update_RASMANCS]
"EnableFileTracing" = "0"

[HKLM\SOFTWARE\Microsoft\Tracing\Windows Update_RASAPI32]
"EnableFileTracing" = "0"

[HKLM\SOFTWARE\Microsoft\Tracing\Windows Update_RASMANCS]
"EnableConsoleTracing" = "0"

[HKCU\Software\Classes\Local Settings\MuiCache\2D\52C64B7E]
"LanguageList" = "en-US, en"

[HKLM\SOFTWARE\Microsoft\Tracing\Windows Update_RASAPI32]
"EnableConsoleTracing" = "0"

[HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced]
"Hidden" = "1"

[HKLM\SOFTWARE\Microsoft\Tracing\Windows Update_RASAPI32]
"ConsoleTracingMask" = "4294901760"
"FileDirectory" = "%windir%\tracing"

"MaxFileSize" = "1048576"
"FileTracingMask" = "4294901760"

[HKLM\SOFTWARE\Microsoft\SystemCertificates\AuthRoot\Certificates\91C6D6EE3E8AC86384E548C299295C756C817B81]
"Blob" = "0F 00 00 00 01 00 00 00 14 00 00 00 85 FE F1 1B"

[HKLM\SOFTWARE\Microsoft\Tracing\Windows Update_RASMANCS]
"MaxFileSize" = "1048576"
"FileTracingMask" = "4294901760"
"ConsoleTracingMask" = "4294901760"
"FileDirectory" = "%windir%\tracing"

The Trojan adds the reference to itself to be executed when a user logs on:

[HKCU\Software\Microsoft\Windows NT\CurrentVersion\Winlogon]
"Shell" = "explorer.exe, C:\Users\"%CurrentUserName%"\AppData\Roaming\Windows Update.exe"

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

[HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
"Windows Update" = "C:\Users\"%CurrentUserName%"\AppData\Roaming\WindowsUpdate.exe"

The Trojan adds the reference to itself to be executed when a user logs on:

[HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
"Shell" = "explorer.exe, C:\Users\"%CurrentUserName%"\AppData\Roaming\Windows Update.exe"

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

[HKLM\SOFTWARE\Microsoft\SystemCertificates\AuthRoot\Certificates]
"91C6D6EE3E8AC86384E548C299295C756C817B81"

The process %original file name%.exe:3400 makes changes in the system registry.
The Trojan creates and/or sets the following values in system registry:

[HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"AutoDetect" = "1"
"UNCAsIntranet" = "0"

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

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"ProxyBypass"

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

[HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap]
"IntranetName"

Dropped PE files

There are no dropped PE files.

HOSTS file anomalies

The Trojan modifies "%System%\drivers\etc\hosts" file which is used to translate DNS entries to IP addresses.
The modified file is 923 bytes in size. The following strings are added to the hosts file listed below:

127.0.0.1 validation.sls.microsoft.com
127.0.0.1 https://pornhub.com/


Rootkit activity

No anomalies have been detected.

Propagation

VersionInfo

No information is available.

PE Sections

Name Virtual Address Virtual Size Raw Size Entropy Section MD5
.text 8192 872996 876544 5.52108 8b4c9ac19e25707649a6754f6aa91ee2
.rsrc 884736 16 4096 0 620f0b67a91f7f74151bc5be745b7110
.reloc 892928 12 4096 0.011373 50edc9e8636df7e223cf5c152270f20e

Dropped from:

Downloaded by:

Similar by SSDeep:

Similar by Lavasoft Polymorphic Checker:

URLs

URL IP
hxxp://whatismyipaddress.com/ 23.223.26.238
hxxp://a767.dspw65.akamai.net/msdownload/update/v3/static/trustedr/en/authrootstl.cab
hxxp://www.download.windowsupdate.com/msdownload/update/v3/static/trustedr/en/authrootstl.cab 62.140.236.163
smtp.mail.com 74.208.5.15
teredo.ipv6.microsoft.com


IDS verdicts (Suricata alerts: Emerging Threats ET ruleset)

Traffic

GET / HTTP/1.1
Host: whatismyipaddress.com
Connection: Keep-Alive


HTTP/1.1 200 OK
Content-Type: text/html
Content-Length: 59
Date: Wed, 30 Aug 2017 07:46:22 GMT
Connection: keep-alive
Access Denied (AK1).  Contact support@whatismyipaddress.comHTTP/1.1 20
0 OK..Content-Type: text/html..Content-Length: 59..Date: Wed, 30 Aug 2
017 07:46:22 GMT..Connection: keep-alive..Access Denied (AK1).  Contac
t support@whatismyipaddress.com..



GET /msdownload/update/v3/static/trustedr/en/authrootstl.cab HTTP/1.1
Cache-Control: max-age = 86402
Connection: Keep-Alive
Accept: */*
If-Modified-Since: Fri, 16 Sep 2016 21:16:59 GMT
If-None-Match: "8017f9a85f10d21:0"
User-Agent: Microsoft-CryptoAPI/6.1
Host: VVV.download.windowsupdate.com


HTTP/1.1 200 OK
Cache-Control: max-age=604800
Content-Type: application/vnd.ms-cab-compressed
Last-Modified: Tue, 13 Jun 2017 19:04:53 GMT
Accept-Ranges: bytes
ETag: "80f83df077e4d21:0"
Server: Microsoft-IIS/8.5
X-Powered-By: ASP.NET
Content-Length: 52967
Date: Wed, 30 Aug 2017 07:46:29 GMT
Connection: keep-alive
X-CCC: UA
X-CID: 2
MSCF............,...................I..................J.` .authroot.s
tl.^R.Y.6..CK...8...........].y.Q..!Jv..%k.....!..DH...B.KBWE.(.f.RQ*.
..f...}'.....x.:.{f...|.s.q..CF.......0....{%i......P.F.yNz:A..L..1..3
...........IG.....4=....~."|..s.|.xuT..._.*.....e.h,....ozs..*.!TmS..A
q... |,.....V..xV....^....FE(.x...N..h...b....y...j.!....7..h. ..@.(V.
.....8..`-..#=.jq'.e...|..X...@...{..rj.d.....?n3.L.......S.......:.O.
.."k.!o......`.l.B 1.....#].....k6.........B.......!P$.A..<..?zk...
.~..P)A0tu....x..-X..E..,a.7,xN..eed.3..L..XT......IG.w_.Y....E....~k.
.X...T.V.g7d.....#.&~.f.O....Dh...x0..J...0..u.dF..P.!..d...%x<!...
....@,...0..3..-.....q.....X.e....A...z.'..2.<.m.f...I.9.z..a.6vo..
 ...P..U7...-.0.Q..<zd!V....=.'.....2H;..5.7.%5PsD.#.....ht%......f
..s.Dp..Lklx%[.!c...I.<...f.<..e.k`......^.......X..?Z...?......
?..I}..5V.v .q.c.9j..Y..J..0U.t./%..Jd @.W.u......U.".)C(........T.4.y
..J.57*^HlY....O|..~\.J]..]e...?..x2c..6.....i.=?x.....N..-X..f"^@'...
.-v..v...7j.Y1.5._v.....*S9.."........%E<E...;p.}........0..P....g.
.@.]E.3........K....K.4V..Q.-,.../.........:.A....Ng,.........BFef.[..
. ..."*...^...L._#:,7..6:.z..!a............E.r>......A....#..c.....
rS.......7.D..JdR.`6.|...>.0....Wf..n..^..8x.4..........-.3y,3.C.(.
...9f...iNK....q....sUq....c...c.....*K.8"..D...<..0............*x,
$x....a....]..p..t.M....6F..u.....p.r.kf...Z......h~.B3...[.....Hc...K
.....I.....%F..:.....N....U..eU........ e. k....3(S..h....1..r..Z.Y...
.....A.i..Z....[%J.....=2"v].....L.P..!........PC*.........j 8.~.)
<<< skipped >>>

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

Windows Update.exe_1588_rwx_00182000_0000B000:

.hP9)h


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):

    vbc.exe:4028
    %original file name%.exe:3400

  2. Delete the original Trojan file.
  3. Delete or disinfect the following files created/modified by the Trojan:

    C:\Users\"%CurrentUserName%"\AppData\Roaming\pid.txt (4 bytes)
    C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Tar24D1.tmp (2712 bytes)
    C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Tar3B40.tmp (2712 bytes)
    C:\Users\"%CurrentUserName%"\AppData\Roaming\WindowsUpdate.exe (7726 bytes)
    C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Cab24BF.tmp (51 bytes)
    C:\Users\"%CurrentUserName%"\AppData\LocalLow\Microsoft\CryptnetUrlCache\Content\94308059B57B3142E455B38A6EB92015 (52 bytes)
    C:\Windows\System32\drivers\etc\hosts (59 bytes)
    C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Cab3B3F.tmp (52 bytes)
    C:\Users\"%CurrentUserName%"\AppData\LocalLow\Microsoft\CryptnetUrlCache\MetaData\94308059B57B3142E455B38A6EB92015 (1720 bytes)
    C:\Users\"%CurrentUserName%"\AppData\Roaming\pidloc.txt (47 bytes)
    C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Cab24D0.tmp (51 bytes)
    C:\Users\"%CurrentUserName%"\AppData\Local\Temp\Tar24C0.tmp (2712 bytes)
    C:\Users\"%CurrentUserName%"\AppData\Local\Temp\holderwb.txt (2 bytes)
    C:\Users\"%CurrentUserName%"\AppData\Roaming\winlogon.exe (7775 bytes)

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

    [HKCU\Software\Microsoft\Windows\CurrentVersion\Run]
    "Windows Update" = "C:\Users\"%CurrentUserName%"\AppData\Roaming\WindowsUpdate.exe"

  5. Remove the references to the Trojan by modifying the following registry value(s) (How to Work with System Registry):

    [HKCU\Software\Microsoft\Windows NT\CurrentVersion\Winlogon]
    "Shell" = "explorer.exe, C:\Users\"%CurrentUserName%"\AppData\Roaming\Windows Update.exe"

    [HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
    "Shell" = "explorer.exe, C:\Users\"%CurrentUserName%"\AppData\Roaming\Windows Update.exe"

  6. Restore the original content of the HOSTS file (%System%\drivers\etc\hosts):
    127.0.0.1 localhost
  7. Clean the Temporary Internet Files folder, which may contain infected files (How to clean Temporary Internet Files folder).
  8. Reboot the computer.

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

No votes yet


Lavasoft is the maker of Ad-Aware, the world's most popular anti-malware software with over 450 million downloads.
© 2025 Lavasoft. All rights reserved.
Terms Of Use |   Privacy Policy


x

Our best antivirus yet!

Fresh new look. Faster scanning. Better protection.

Enjoy unique new features, lightning fast scans and a simple yet beautiful new look in our best antivirus yet!

For a quicker, lighter and more secure experience, download the all new adaware antivirus 12 now!

Download adaware antivirus 12
No thanks, continue to lavasoft.com
close x

Discover the new adaware antivirus 12

Our best antivirus yet

Download Now