Class: Trojan
A malicious program designed to electronically spy on the user’s activities (intercept keyboard input, take screenshots, capture a list of active applications, etc.). The collected information is sent to the cybercriminal by various means, including email, FTP, and HTTP (by sending data in a request).Read more
Platform: Win32
Win32 is an API on Windows NT-based operating systems (Windows XP, Windows 7, etc.) that supports execution of 32-bit applications. One of the most widespread programming platforms in the world.Family: Kolweb
No family descriptionExamples
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Tactics and Techniques: Mitre*
Adversaries may establish persistence by executing malicious content triggered by user inactivity. Screensavers are programs that execute after a configurable time of user inactivity and consist of Portable Executable (PE) files with a .scr file extension.(Citation: Wikipedia Screensaver) The Windows screensaver application scrnsave.scr is located in C:WindowsSystem32, and C:WindowssysWOW64 on 64-bit Windows systems, along with screensavers included with base Windows installations.
The following screensaver settings are stored in the Registry (HKCUControl PanelDesktop) and could be manipulated to achieve persistence:
* SCRNSAVE.exe – set to malicious PE path
* ScreenSaveActive – set to ‘1’ to enable the screensaver
* ScreenSaverIsSecure – set to ‘0’ to not require a password to unlock
* ScreenSaveTimeout – sets user inactivity timeout before screensaver is executed
Adversaries can use screensaver settings to maintain persistence by setting the screensaver to run malware after a certain timeframe of user inactivity.(Citation: ESET Gazer Aug 2017)
Adversaries may establish persistence by executing malicious content triggered by user inactivity. Screensavers are programs that execute after a configurable time of user inactivity and consist of Portable Executable (PE) files with a .scr file extension.(Citation: Wikipedia Screensaver) The Windows screensaver application scrnsave.scr is located in C:WindowsSystem32, and C:WindowssysWOW64 on 64-bit Windows systems, along with screensavers included with base Windows installations.
The following screensaver settings are stored in the Registry (HKCUControl PanelDesktop) and could be manipulated to achieve persistence:
* SCRNSAVE.exe – set to malicious PE path
* ScreenSaveActive – set to ‘1’ to enable the screensaver
* ScreenSaverIsSecure – set to ‘0’ to not require a password to unlock
* ScreenSaveTimeout – sets user inactivity timeout before screensaver is executed
Adversaries can use screensaver settings to maintain persistence by setting the screensaver to run malware after a certain timeframe of user inactivity.(Citation: ESET Gazer Aug 2017)
Adversaries may establish persistence by executing malicious content triggered by user inactivity. Screensavers are programs that execute after a configurable time of user inactivity and consist of Portable Executable (PE) files with a .scr file extension.(Citation: Wikipedia Screensaver) The Windows screensaver application scrnsave.scr is located in C:WindowsSystem32, and C:WindowssysWOW64 on 64-bit Windows systems, along with screensavers included with base Windows installations.
The following screensaver settings are stored in the Registry (HKCUControl PanelDesktop) and could be manipulated to achieve persistence:
* SCRNSAVE.exe – set to malicious PE path
* ScreenSaveActive – set to ‘1’ to enable the screensaver
* ScreenSaverIsSecure – set to ‘0’ to not require a password to unlock
* ScreenSaveTimeout – sets user inactivity timeout before screensaver is executed
Adversaries can use screensaver settings to maintain persistence by setting the screensaver to run malware after a certain timeframe of user inactivity.(Citation: ESET Gazer Aug 2017)
Adversaries may establish persistence by executing malicious content triggered by user inactivity. Screensavers are programs that execute after a configurable time of user inactivity and consist of Portable Executable (PE) files with a .scr file extension.(Citation: Wikipedia Screensaver) The Windows screensaver application scrnsave.scr is located in C:WindowsSystem32, and C:WindowssysWOW64 on 64-bit Windows systems, along with screensavers included with base Windows installations.
The following screensaver settings are stored in the Registry (HKCUControl PanelDesktop) and could be manipulated to achieve persistence:
* SCRNSAVE.exe – set to malicious PE path
* ScreenSaveActive – set to ‘1’ to enable the screensaver
* ScreenSaverIsSecure – set to ‘0’ to not require a password to unlock
* ScreenSaveTimeout – sets user inactivity timeout before screensaver is executed
Adversaries can use screensaver settings to maintain persistence by setting the screensaver to run malware after a certain timeframe of user inactivity.(Citation: ESET Gazer Aug 2017)
Adversaries may abuse Regsvr32.exe to proxy execution of malicious code. Regsvr32.exe is a command-line program used to register and unregister object linking and embedding controls, including dynamic link libraries (DLLs), on Windows systems. The Regsvr32.exe binary may also be signed by Microsoft. (Citation: Microsoft Regsvr32)
Malicious usage of Regsvr32.exe may avoid triggering security tools that may not monitor execution of, and modules loaded by, the regsvr32.exe process because of allowlists or false positives from Windows using regsvr32.exe for normal operations. Regsvr32.exe can also be used to specifically bypass application control using functionality to load COM scriptlets to execute DLLs under user permissions. Since Regsvr32.exe is network and proxy aware, the scripts can be loaded by passing a uniform resource locator (URL) to file on an external Web server as an argument during invocation. This method makes no changes to the Registry as the COM object is not actually registered, only executed. (Citation: LOLBAS Regsvr32) This variation of the technique is often referred to as a “Squiblydoo” and has been used in campaigns targeting governments. (Citation: Carbon Black Squiblydoo Apr 2016) (Citation: FireEye Regsvr32 Targeting Mongolian Gov)
Regsvr32.exe can also be leveraged to register a COM Object used to establish persistence via Component Object Model Hijacking. (Citation: Carbon Black Squiblydoo Apr 2016)
Adversaries may abuse Regsvr32.exe to proxy execution of malicious code. Regsvr32.exe is a command-line program used to register and unregister object linking and embedding controls, including dynamic link libraries (DLLs), on Windows systems. The Regsvr32.exe binary may also be signed by Microsoft. (Citation: Microsoft Regsvr32)
Malicious usage of Regsvr32.exe may avoid triggering security tools that may not monitor execution of, and modules loaded by, the regsvr32.exe process because of allowlists or false positives from Windows using regsvr32.exe for normal operations. Regsvr32.exe can also be used to specifically bypass application control using functionality to load COM scriptlets to execute DLLs under user permissions. Since Regsvr32.exe is network and proxy aware, the scripts can be loaded by passing a uniform resource locator (URL) to file on an external Web server as an argument during invocation. This method makes no changes to the Registry as the COM object is not actually registered, only executed. (Citation: LOLBAS Regsvr32) This variation of the technique is often referred to as a “Squiblydoo” and has been used in campaigns targeting governments. (Citation: Carbon Black Squiblydoo Apr 2016) (Citation: FireEye Regsvr32 Targeting Mongolian Gov)
Regsvr32.exe can also be leveraged to register a COM Object used to establish persistence via Component Object Model Hijacking. (Citation: Carbon Black Squiblydoo Apr 2016)
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