BKDR_BLADABI.AC


 ALIASES:

Backdoor:MSIL/Bladabindi (Microsoft); Trojan-Dropper.Win32.Dorifel.apnx (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan horse BackDoor.Generic18.BGVM (AVG)

 PLATFORM:

Windows

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW


This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

  TECHNICAL DETAILS

File Size:

1,688,172 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

09 Feb 2015

Arrival Details

This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This backdoor creates the following folders:

  • %User Temp%\$inst
  • %Program Files%\skype technologie S.A
  • %Program Files%\skype technologie S.A\SkypeSetup

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %Program Files% is the Program Files folder, where it usually is C:\Program Files on all Windows operating system versions; C:\Program Files (x86) for 32-bit applications running on Windows 64-bit operating systems.)

Autostart Technique

This backdoor adds the following registry entries to enable its automatic execution at every system startup:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
e62976a12d4e296c9ac3ee229a4c09a3 = "%User Profile%\vcl.exe .."

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
e62976a12d4e296c9ac3ee229a4c09a3 = "%User Profile%\vcl.exe .."

Other System Modifications

This backdoor deletes the following files:

  • %User Temp%\$inst\0.tmp
  • %User Temp%\$inst\1.tmp
  • %User Temp%\$inst\3.tmp
  • %User Temp%\$inst\4.tmp
  • %User Temp%\$inst\5.tmp
  • %User Temp%\$inst\6.tmp
  • %User Temp%\$inst\7.tmp
  • %User Temp%\$inst\8.tmp
  • %User Temp%\$inst\9.tmp
  • %User Temp%\$inst\10.tmp
  • %User Temp%\$inst\11.tmp
  • %User Temp%\$inst\12.tmp
  • %User Temp%\$inst\13.tmp
  • %User Temp%\$inst\14.tmp
  • %User Temp%\$inst\15.tmp
  • %User Temp%\$inst\16.tmp
  • %User Temp%\$inst\17.tmp
  • %User Temp%\$inst\20.tmp
  • %User Temp%\$inst\50.tmp
  • %User Temp%\$inst\21.tmp
  • %User Temp%\$inst\51.tmp
  • %User Temp%\$inst\22.tmp
  • %User Temp%\$inst\52.tmp
  • %User Temp%\$inst\23.tmp
  • %User Temp%\$inst\53.tmp
  • %User Temp%\$inst\24.tmp
  • %User Temp%\$inst\54.tmp
  • %User Temp%\$inst\25.tmp
  • %User Temp%\$inst\55.tmp
  • %User Temp%\$inst\26.tmp
  • %User Temp%\$inst\56.tmp
  • %User Temp%\$inst\27.tmp
  • %User Temp%\$inst\57.tmp
  • %User Temp%\$inst\28.tmp
  • %User Temp%\$inst\58.tmp
  • %User Temp%\$inst\29.tmp
  • %User Temp%\$inst\59.tmp
  • %User Temp%\$inst\30.tmp
  • %User Temp%\$inst\60.tmp
  • %User Temp%\$inst\31.tmp
  • %User Temp%\$inst\61.tmp
  • %User Temp%\$inst\32.tmp
  • %User Temp%\$inst\62.tmp
  • %User Temp%\$inst\33.tmp
  • %User Temp%\$inst\63.tmp
  • %User Temp%\$inst\34.tmp
  • %User Temp%\$inst\64.tmp
  • %User Temp%\$inst\35.tmp
  • %User Temp%\$inst\65.tmp
  • %User Temp%\$inst\36.tmp
  • %User Temp%\$inst\66.tmp
  • %User Temp%\$inst\37.tmp
  • %User Temp%\$inst\67.tmp
  • %User Temp%\$inst\38.tmp
  • %User Temp%\$inst\68.tmp
  • %User Temp%\$inst\39.tmp
  • %User Temp%\$inst\69.tmp
  • %User Temp%\$inst\40.tmp
  • %User Temp%\$inst\70.tmp
  • %User Temp%\$inst\41.tmp
  • %User Temp%\$inst\71.tmp
  • %User Temp%\$inst\42.tmp
  • %User Temp%\$inst\72.tmp
  • %User Temp%\$inst\43.tmp
  • %User Temp%\$inst\73.tmp
  • %User Temp%\$inst\44.tmp
  • %User Temp%\$inst\74.tmp
  • %User Temp%\$inst\45.tmp
  • %User Temp%\$inst\75.tmp

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

It adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Phone\UI

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Phone\UI\General

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22
DisplayName = "SkypeSetup 7.0.0.22"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22
DisplayVersion = "7.0.0.22"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22
VersionMajor = "7"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22
VersionMinor = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22
Publisher = "skype technologie S.A"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22
DisplayIcon = "%Program Files%\skype technologie S.A\SkypeSetup\Uninstall.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22
UninstallString = "%Program Files%\skype technologie S.A\SkypeSetup\Uninstall.exe"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22
URLInfoAbout = "http://www.SKYPE.com"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22
HelpLink = "mailto:support@SKYPE.com"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22
InstallLocation = "%Program Files%\skype technologie S.A\SkypeSetup"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22
InstallDate = "20150105"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22
Language = "49"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22
EstimatedSize = "799"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22
NoModify = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
SkypeSetup 7.0.0.22
NoRepair = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Phone\UI
InstallExitCode = "c351"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Phone\UI\General
SkypeSetup = "SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnce"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
BINGSRCHFF = "ff"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
BINGSRCHIE = "ff"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
BINGSRCHGC = "ff"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
MSNHPFF = "ff"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
MSNHPIE = "ff"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
MSNHPGC = "ff"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
BINGSRCHFF = "14"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
BINGSRCHIE = "14"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
BINGSRCHGC = "14"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
MSNHPFF = "14"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
MSNHPIE = "14"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
MSNHPGC = "14"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
BINGSRCHFF = "15"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
BINGSRCHIE = "15"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
BINGSRCHGC = "15"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
MSNHPFF = "15"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
MSNHPIE = "15"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
MSNHPGC = "15"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
MSNHPIE = "7"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
MSNHPFF = "7"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
MSNHPGC = "7"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
BINGSRCHIE = "7"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
BINGSRCHFF = "7"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
BINGSRCHGC = "7"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
YHP = "ff"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
YSRCH = "ff"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
YHP = "7"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
YSRCH = "7"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
C2CFF = "ff"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
C2CIE = "ff"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
C2CGC = "ff"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
C2CFF = "8"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
C2CGC = "8"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Phone\UI
InstallExitCode = "c357"

HKEY_LOCAL_MACHINE\SOFTWARE\Skype\
Installer
DownloadContentLength = "0"

HKEY_CURRENT_USER\Environment
SEE_MASK_NOZONECHECKS = "1"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%User Profile%\vcl.exe = "%User Profile%\vcl.exe:*:Enabled:vcl.exe"

Dropping Routine

This backdoor drops the following files:

  • %User Temp%\$inst\2.tmp
  • %User Temp%\$inst\temp_0.tmp
  • %Program Files%\skype technologie S.A\SkypeSetup\Uninstall.ini
  • %User Temp%\DefaultPackOffer.dll
  • %User Profile%\vcl.exe.tmp
  • %User Profile%\vcl.exe

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %Program Files% is the Program Files folder, where it usually is C:\Program Files on all Windows operating system versions; C:\Program Files (x86) for 32-bit applications running on Windows 64-bit operating systems.. %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)

Other Details

This backdoor connects to the following possibly malicious URL:

  • http://ui.{BLOCKED}e.com/ui/0/7.0.0.102/en/lightinstaller?source=lightinstaller
  • {BLOCKED}0.1

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.700

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 key

[ 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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall
    • SkypeSetup 7.0.0.22
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Phone
    • UI
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Phone\UI
    • General
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype
    • Installer

Step 4

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\Windows\CurrentVersion\Run
    • e62976a12d4e296c9ac3ee229a4c09a3 = "%User Profile%\vcl.exe .."
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
    • e62976a12d4e296c9ac3ee229a4c09a3 = "%User Profile%\vcl.exe .."
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SkypeSetup 7.0.0.22
    • DisplayName = "SkypeSetup 7.0.0.22"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SkypeSetup 7.0.0.22
    • DisplayVersion = "7.0.0.22"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SkypeSetup 7.0.0.22
    • VersionMajor = "7"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SkypeSetup 7.0.0.22
    • VersionMinor = "0"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SkypeSetup 7.0.0.22
    • Publisher = "skype technologie S.A"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SkypeSetup 7.0.0.22
    • DisplayIcon = "%Program Files%\skype technologie S.A\SkypeSetup\Uninstall.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SkypeSetup 7.0.0.22
    • UninstallString = "%Program Files%\skype technologie S.A\SkypeSetup\Uninstall.exe"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SkypeSetup 7.0.0.22
    • URLInfoAbout = "http://www.SKYPE.com"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SkypeSetup 7.0.0.22
    • HelpLink = "mailto:support@SKYPE.com"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SkypeSetup 7.0.0.22
    • InstallLocation = "%Program Files%\skype technologie S.A\SkypeSetup"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SkypeSetup 7.0.0.22
    • InstallDate = "20150105"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SkypeSetup 7.0.0.22
    • Language = "49"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SkypeSetup 7.0.0.22
    • EstimatedSize = "799"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SkypeSetup 7.0.0.22
    • NoModify = "1"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SkypeSetup 7.0.0.22
    • NoRepair = "1"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Phone\UI
    • InstallExitCode = "c351"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Phone\UI\General
    • SkypeSetup = "SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnce"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • BINGSRCHFF = "ff"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • BINGSRCHIE = "ff"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • BINGSRCHGC = "ff"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • MSNHPFF = "ff"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • MSNHPIE = "ff"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • MSNHPGC = "ff"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • BINGSRCHFF = "14"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • BINGSRCHIE = "14"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • BINGSRCHGC = "14"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • MSNHPFF = "14"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • MSNHPIE = "14"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • MSNHPGC = "14"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • BINGSRCHFF = "15"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • BINGSRCHIE = "15"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • BINGSRCHGC = "15"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • MSNHPFF = "15"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • MSNHPIE = "15"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • MSNHPGC = "15"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • MSNHPIE = "7"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • MSNHPFF = "7"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • MSNHPGC = "7"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • BINGSRCHIE = "7"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • BINGSRCHFF = "7"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • BINGSRCHGC = "7"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • YHP = "ff"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • YSRCH = "ff"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • YHP = "7"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • YSRCH = "7"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • C2CFF = "ff"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • C2CIE = "ff"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • C2CGC = "ff"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • C2CFF = "8"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • C2CGC = "8"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Phone\UI
    • InstallExitCode = "c357"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Skype\Installer
    • DownloadContentLength = "0"
  • In HKEY_CURRENT_USER\Environment
    • SEE_MASK_NOZONECHECKS = "1"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List
    • %User Profile%\vcl.exe = "%User Profile%\vcl.exe:*:Enabled:vcl.exe"

Step 5

Search and delete these components

[ Learn More ]
There may be some components that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.
  • %User Temp%\$inst\2.tmp
  • %User Temp%\$inst\temp_0.tmp
  • %Program Files%\skype technologie S.A\SkypeSetup\Uninstall.ini
  • %User Temp%\DefaultPackOffer.dll
  • %User Profile%\vcl.exe.tmp
  • %User Profile%\vcl.exe

Step 6

Search and delete these folders

[ 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.
  • %User Temp%\$inst
  • %Program Files%\skype technologie S.A
  • %Program Files%\skype technologie S.A\SkypeSetup

Step 7

Restart in normal mode and scan your computer with your Trend Micro product for files detected as BKDR_BLADABI.AC. 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.

Step 8

Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.

  • %User Temp%\$inst\0.tmp
  • %User Temp%\$inst\1.tmp
  • %User Temp%\$inst\3.tmp
  • %User Temp%\$inst\4.tmp
  • %User Temp%\$inst\5.tmp
  • %User Temp%\$inst\6.tmp
  • %User Temp%\$inst\7.tmp
  • %User Temp%\$inst\8.tmp
  • %User Temp%\$inst\9.tmp
  • %User Temp%\$inst\10.tmp
  • %User Temp%\$inst\11.tmp
  • %User Temp%\$inst\12.tmp
  • %User Temp%\$inst\13.tmp
  • %User Temp%\$inst\14.tmp
  • %User Temp%\$inst\15.tmp
  • %User Temp%\$inst\16.tmp
  • %User Temp%\$inst\17.tmp
  • %User Temp%\$inst\20.tmp
  • %User Temp%\$inst\50.tmp
  • %User Temp%\$inst\21.tmp
  • %User Temp%\$inst\51.tmp
  • %User Temp%\$inst\22.tmp
  • %User Temp%\$inst\52.tmp
  • %User Temp%\$inst\23.tmp
  • %User Temp%\$inst\53.tmp
  • %User Temp%\$inst\24.tmp
  • %User Temp%\$inst\54.tmp
  • %User Temp%\$inst\25.tmp
  • %User Temp%\$inst\55.tmp
  • %User Temp%\$inst\26.tmp
  • %User Temp%\$inst\56.tmp
  • %User Temp%\$inst\27.tmp
  • %User Temp%\$inst\57.tmp
  • %User Temp%\$inst\28.tmp
  • %User Temp%\$inst\58.tmp
  • %User Temp%\$inst\29.tmp
  • %User Temp%\$inst\59.tmp
  • %User Temp%\$inst\30.tmp
  • %User Temp%\$inst\60.tmp
  • %User Temp%\$inst\31.tmp
  • %User Temp%\$inst\61.tmp
  • %User Temp%\$inst\32.tmp
  • %User Temp%\$inst\62.tmp
  • %User Temp%\$inst\33.tmp
  • %User Temp%\$inst\63.tmp
  • %User Temp%\$inst\34.tmp
  • %User Temp%\$inst\64.tmp
  • %User Temp%\$inst\35.tmp
  • %User Temp%\$inst\65.tmp
  • %User Temp%\$inst\36.tmp
  • %User Temp%\$inst\66.tmp
  • %User Temp%\$inst\37.tmp
  • %User Temp%\$inst\67.tmp
  • %User Temp%\$inst\38.tmp
  • %User Temp%\$inst\68.tmp
  • %User Temp%\$inst\39.tmp
  • %User Temp%\$inst\69.tmp
  • %User Temp%\$inst\40.tmp
  • %User Temp%\$inst\70.tmp
  • %User Temp%\$inst\41.tmp
  • %User Temp%\$inst\71.tmp
  • %User Temp%\$inst\42.tmp
  • %User Temp%\$inst\72.tmp
  • %User Temp%\$inst\43.tmp
  • %User Temp%\$inst\73.tmp
  • %User Temp%\$inst\44.tmp
  • %User Temp%\$inst\74.tmp
  • %User Temp%\$inst\45.tmp
  • %User Temp%\$inst\75.tmp


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