TSPY_KRONOS.B
Windows
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Spyware
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
Dropped by other malware, Downloaded from the Internet
This spyware 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
406,882 bytes
EXE
Yes
18 Nov 2016
Steals information
Arrival Details
This spyware 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 spyware drops the following copies of itself into the affected system:
- %Application Data%\Microsoft\{GUID}\{random 8 alphanumeric characters}.exe
(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming 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 drops the following files:
- %Application Data%\Mozilla\Firefox\Profiles\{All Folders}\user.js
(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming 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 processes:
- %System%\svchost.exe
(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)
It injects itself into the following processes as part of its memory residency routine:
- added svchost.exe
- all running processes except chrome.exe and explorer.exe
Autostart Technique
This spyware adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random 8 alphanumeric characters} = %Application Data%\Microsoft\{GUID}\{random 8 alphanumeric characters}.exe
HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\Run
{random 8 alphanumeric characters} = %Application Data%\Microsoft\{GUID}\{random 8 alphanumeric characters}.exe
Other System Modifications
This spyware adds the following registry entries:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion
{random 8 alphanumeric characters} = {GUID}
HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion
{random 8 alphanumeric characters} = {GUID}
Other Details
This spyware does the following:
- It lowers the security of Mozilla Firefox browser.
- It checks for existence of virtual environment.
- It has the capability of stealing credentials from browsers.
SOLUTION
9.800
12.906.02
18 Nov 2016
12.907.00
19 Nov 2016
Step 1
Trend Micro products with the XGen technology detect this malware as
- TROJ.WIN32.TRX.XXPE0007
Step 2
Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.
Step 3
Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.
Step 4
Restart in Safe Mode
Step 5
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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
- {random 8 alphanumeric characters} = %Application Data%\Microsoft\{GUID}\{random 8 alphanumeric characters}.exe
- {random 8 alphanumeric characters} = %Application Data%\Microsoft\{GUID}\{random 8 alphanumeric characters}.exe
- In HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
- {random 8 alphanumeric characters} = %Application Data%\Microsoft\{GUID}\{random 8 alphanumeric characters}.exe
- {random 8 alphanumeric characters} = %Application Data%\Microsoft\{GUID}\{random 8 alphanumeric characters}.exe
- In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion
- {random 8 alphanumeric characters} = {GUID}
- {random 8 alphanumeric characters} = {GUID}
- In HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion
- {random 8 alphanumeric characters} = {GUID}
- {random 8 alphanumeric characters} = {GUID}
Step 6
Search and delete this file
- %Application Data%\Mozilla\Firefox\Profiles\{All Folders}\user.js
Step 7
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TSPY_KRONOS.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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