TROJ_TEERAC.B
Ransom:Win32/Teerac.C (Microsoft); RDN/Ransom!el (McAfee); Backdoor.Trojan (Symantec); Trojan-Ransom.Win32.Foreign.lgqc (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Win32/Cryptor (AVG)
Windows
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Trojan
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This Trojan 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
Arrival Details
This Trojan 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 Trojan creates the following folders:
- %User Profile%\Application Data\uluxohydelujynyf
(Note: %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.)
Autostart Technique
This Trojan adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
ozgtelok = "%Windows%\uzwlurel.exe"
Other System Modifications
This Trojan modifies the following registry entries:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.imaadpcm
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.imaadpcm
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.imaadpcm
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.imaadpcm
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msadpcm
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msadpcm
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msadpcm
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msadpcm
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg711
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg711
cFormatTags = "3"
(Note: The default value data of the said registry entry is 3.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg711
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg711
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msgsm610
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msgsm610
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msgsm610
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msgsm610
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.trspch
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.trspch
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.trspch
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.trspch
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg723
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg723
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg723
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msg723
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msaudio1
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msaudio1
cFormatTags = "3"
(Note: The default value data of the said registry entry is 3.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msaudio1
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.msaudio1
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.sl_anet
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.sl_anet
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.sl_anet
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.sl_anet
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.iac2
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.iac2
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.iac2
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.iac2
cFilterTags = "0"
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.l3acm
fdwSupport = "1"
(Note: The default value data of the said registry entry is 1.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.l3acm
cFormatTags = "2"
(Note: The default value data of the said registry entry is 2.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.l3acm
aFormatTagCache = "{random values}"
(Note: The default value data of the said registry entry is {random values}.)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
AudioCompressionManager\DriverCache\msacm.l3acm
cFilterTags = "0"
Dropping Routine
This Trojan drops the following files:
- %User Profile%\uluxohydelujynyf\01000000
- %Windows%\uzwlurel.exe
- %User Profile%\uluxohydelujynyf\02000000
- %User Profile%\uluxohydelujynyf\00000000
(Note: %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.. %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.)
This report is generated via an automated analysis system.
SOLUTION
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
Step 3
Delete this registry value
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\Run
- ozgtelok = "%Windows%\uzwlurel.exe"
Step 4
Restore these modified registry values
Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.imaadpcm
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.imaadpcm
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.imaadpcm
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.imaadpcm
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msadpcm
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msadpcm
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msadpcm
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msadpcm
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg711
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg711
- From: cFormatTags = "3"
To: cFormatTags = ""3""
- From: cFormatTags = "3"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg711
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg711
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msgsm610
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msgsm610
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msgsm610
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msgsm610
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.trspch
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.trspch
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.trspch
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.trspch
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg723
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg723
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg723
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msg723
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msaudio1
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msaudio1
- From: cFormatTags = "3"
To: cFormatTags = ""3""
- From: cFormatTags = "3"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msaudio1
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.msaudio1
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.sl_anet
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.sl_anet
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.sl_anet
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.sl_anet
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.iac2
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.iac2
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.iac2
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.iac2
- cFilterTags = "0"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.l3acm
- From: fdwSupport = "1"
To: fdwSupport = ""1""
- From: fdwSupport = "1"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.l3acm
- From: cFormatTags = "2"
To: cFormatTags = ""2""
- From: cFormatTags = "2"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.l3acm
- From: aFormatTagCache = "{random values}"
To: aFormatTagCache = ""{random values}""
- From: aFormatTagCache = "{random values}"
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\AudioCompressionManager\DriverCache\msacm.l3acm
- cFilterTags = "0"
Step 5
Search and delete these components
- %User Profile%\uluxohydelujynyf\01000000
- %Windows%\uzwlurel.exe
- %User Profile%\uluxohydelujynyf\02000000
- %User Profile%\uluxohydelujynyf\00000000
Step 6
Search and delete this folder
- %User Profile%\Application Data\uluxohydelujynyf
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_TEERAC.B. 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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