TROJ_CRYPTR.SMAM

 Analysis by: Erika Bianca Mendoza

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

This Trojan may be unknowingly downloaded by a user while visiting malicious websites.

It also has rootkit capabilities, which enables it to hide its processes and files from the user.

  TECHNICAL DETAILS

File Size:

344,712 bytes

File Type:

EXE

File Compression:

UPX

Memory Resident:

Yes

Initial Samples Received Date:

12 Apr 2011

Payload:

Hides files and processes, Steals information, Compromises system security

Arrival Details

This Trojan may be unknowingly downloaded by a user while visiting malicious websites.

Installation

This Trojan drops the following files:

  • %System Root%\recyclebin\config.bin

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

It drops the following copies of itself into the affected system:

  • %System Root%\recyclebin\recyclebin.exe

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

It creates the following folders with attributes set to System and Hidden to prevent users from discovering and removing its components:

  • %System Root%\recyclebin

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

It adds the following mutexes to ensure that only one of its copies runs at any one time:

  • scandisking

It injects itself into the following processes as part of its memory residency routine:

  • explorer.exe

Other System Modifications

This Trojan adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\PhishingFilter
EnabledV8 = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\PhishingFilter
ShownServiceDownBalloon = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Recovery
ClearBrowsingHistoryOnExit = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
GlobalUserOffline = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
ProxyHttp1.1 = "1"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
WarnOnPostRedirect = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings
WarnOnIntranet = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\0
1409 = "3"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\1
1409 = "3"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\2
1409 = "3"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\3
1409 = "3"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Internet Settings\
Zones\4
1409 = "3"

Rootkit Capabilities

This Trojan also has rootkit capabilities, which enables it to hide its processes and files from the user.

Information Theft

This Trojan monitors the Internet Explorer (IE) activities of the affected system, specifically the address bar or title bar. It recreates a legitimate website with a spoofed login page if a user visits banking sites with the following strings in the address bar or title bar:

  • https://*sparkasse*/
  • https://*ksk-*/
  • https://*spk-*/
  • https://*ssk-*/
  • https://*sparkasse*de
  • https://*ksk-*de
  • https://*spk-*de
  • https://*ssk-*de
  • https://*portal*/portal/login
  • https://*portal*/portal/
  • https://*portal*/portal
  • https://*portal*/portal/Starten*
  • ttps://*portal*/portal/Login*
  • https://banking.*/cgi/anfang.cgi*
  • https://banking.*/cgi/login.cgi*
  • https://*-*/pintan/index.php
  • https://*/v6/banking/*
  • https://*/v6/home/*
  • https://banking.sparkasse.de/cgi/beenden.cgi
  • http://*/homepage/banking/1.html
  • http://*/privatkunden/0.html
  • http://raiba-nu-wh.net/banking.html
  • https://www.vrb-ismaning.de/index.php?id=*
  • http://*.de/ebanking.cfm?CFID=*&CFTOKEN=*
  • http://*/online_banking/anmeldung.html
  • http://*/banking___services/anmeldung.html
  • https://*/entry?bankid=*&appid=*
  • https://*/entry?appid=*&bankid=*
  • https://*/entry?rzid=XC&rzbk=*
  • https://*bank*.de/entry?bankid=*& ppid=*
  • https://*bank*.de/*/entry?rzid=XC&rzbk=*
  • https://internetbanking.gad.de/ptlweb/WebPortal?bankid=*
  • https://internetbanking.gad.de/banking/portal?bankid=*
  • https://internetbanking.gad.de/wrs/ptlweb/WebPortal?bankidTimeout=hilfesicher&applId=ib_hilfe&frame=newwin
  • https://www.brokerage.vr-networld.de/*bankid=*
  • https://internetbanking.gad.de/*/csshover.htc
  • https://banking.postbank.de/app/welcome.do
  • https://banking.postbank.de/app/mobile/35345365.sisx
  • https://banking.postbank.de/app/login.do
  • https://banking.postbank.de/app/
  • http://sparkasse.de/images/zumfinanzstatus.gif
  • http://www.postbank.de/csmedia/
  • http://www.postbank.de/*mtan/so_gehts.html*
  • https://banking.postba k.de/app/mtan.listen.input.do/*.

Other Details

This Trojan does the following:

  • Injects its code into all running processes except:
    • csrss.exe
    • smss.exe
    • system
  • Hooks the following APIs to hide its files:
    • NtQueryDirectoryFile
    • NtResumeThread
    • NtVdmControl
  • Hooks also the following APIs:
    • ADVAPI32.dll
    • CRYPT32.dll
    • CryptEncrypt
    • FlushInstructionCache
    • HttpAddRequestHeadersA
    • HttpOpenRequestA
    • HttpQueryInfoA
    • HttpSendRequestA
    • HttpSendRequestW
    • InternetCloseHandle
    • InternetQueryDataAvailable
    • InternetQueryOptionA
    • InternetReadFile
    • InternetReadFileExA
    • InternetWriteFile
    • kernel32.dll
    • ntdll.dll
    • NtEnumerateValueKey
    • NtSetInformationFile
    • PFXImportCertStore
    • send
    • TranslateMessage
    • USER32.dll
    • WININET.dll
    • WS2_32.dll
  • Steals FTP, POP3 accounts and certificates
  • Captures entered information in web forms
  • Performs Web injects/Web fakes
  • Connects to the following malicious server where it receives commands from a remote malicious user:
    • http://{BLOCKED}aha.com

  SOLUTION

Minimum Scan Engine:

8.900

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Restart in Safe Mode

[ Learn More ]

Step 3

Delete this registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

 
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\PhishingFilter
    • EnabledV8 = 0
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\PhishingFilter
    • ShownServiceDownBalloon = 0
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Recovery
    • ClearBrowsingHistoryOnExit = 0
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings
    • GlobalUserOffline = 0
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings
    • ProxyHttp1.1 = 1
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings
    • WarnOnPostRedirect = 0
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings
    • WarnOnIntranet = 0
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\0
    • 1409 = 3
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\1
    • 1409 = 3
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\2
    • 1409 = 3
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\3
    • 1409 = 3
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings\Zones\4
    • 1409 = 3

Step 4

Search and delete this folder

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %System Root%\recyclebin

Step 5

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_CRYPTR.SMAM. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.


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