Analysis by: Paul Steven Nadera
ALIASES:

PUA.InstallCore (Ikarus); Win32/InstallCore.Gen.A potentially unwanted application (NOD32)

 PLATFORM:

Windows

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

  • Threat Type: Potentially Unwanted Application

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel: Downloaded from the Internet

This Potentially Unwanted Application arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites. It may be manually installed by a user.

As of this writing, the said sites are inaccessible.

It connects to certain websites to send and receive information.

  TECHNICAL DETAILS

File Size: 808,768 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 06 Oct 2020
Payload: Connects to URLs/IPs, Displays graphics/image

Arrival Details

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

It may be manually installed by a user.

Installation

This Potentially Unwanted Application drops the following files:

  • %User Temp%\is{random characters}\css\ie6_main.css
  • %User Temp%\is{random characters}\css\main.css
  • %User Temp%\is{random characters}\css\sdk-ui\browse.css
  • %User Temp%\is{random characters}\css\sdk-ui\button.css
  • %User Temp%\is{random characters}\css\sdk-ui\checkbox.css
  • %User Temp%\is{random characters}\css\sdk-ui\images\button-bg.png
  • %User Temp%\is{random characters}\css\sdk-ui\images\progress-bg-corner.png
  • %User Temp%\is{random characters}\css\sdk-ui\images\progress-bg.png
  • %User Temp%\is{random characters}\css\sdk-ui\images\progress-bg2.png
  • %User Temp%\is{random characters}\css\sdk-ui\progress-bar.css
  • %User Temp%\is{random characters}\csshover3.htc
  • %User Temp%\is{random characters}\dat\upd.DAT
  • %User Temp%\is{random characters}\form.bmp.Mask
  • %User Temp%\is{random characters}\images\BG.png
  • %User Temp%\is{random characters}\images\Close.png
  • %User Temp%\is{random characters}\images\Close_Hover.png
  • %User Temp%\is{random characters}\images\Color_Button.png
  • %User Temp%\is{random characters}\images\Color_Button_Hover.png
  • %User Temp%\is{random characters}\images\Grey_Button.png
  • %User Temp%\is{random characters}\images\Grey_Button_Hover.png
  • %User Temp%\is{random characters}\images\Loader.gif
  • %User Temp%\is{random characters}\images\Logo.png
  • %User Temp%\is{random characters}\images\Progress.png
  • %User Temp%\is{random characters}\images\ProgressBar.png
  • %User Temp%\is{random characters}\images\text-bg.png
  • %User Temp%\is{random characters}\locale\DE.locale
  • %User Temp%\is{random characters}\locale\EN.locale
  • %User Temp%\is{random characters}\locale\ES.locale
  • %User Temp%\is{random characters}\locale\FR.locale
  • %User Temp%\is{random characters}\locale\IT.locale
  • %User Temp%\is{random characters}\locale\PL.locale
  • %User Temp%\is{random characters}\locale\PT.locale
  • %User Temp%\is{random characters}\locale\RU.locale
  • %User Temp%\is{random characters}\locale\UA.locale
  • %User Temp%\is{random characters}\bootstrap_34102.html
  • %User Temp%\{random characters}.log
  • %User Temp%\ICReinstall_{grayware filename}.exe
  • %User Temp%\is1242154493\2042623_stp.EXE
  • %User Temp%\is1242154493\2042623_stp.EXE.part
  • %Desktop%\Continue Pdf Creator Installation.lnk
  • %Program Files%\is{random characters}.log

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %Desktop% is the current user's desktop, which is usually C:\Documents and Settings\{User Name}\Desktop on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\Desktop on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000(32-bit), Server 2003(32-bit), XP, Vista(64-bit), 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit) , or C:\Program Files (x86) in Windows XP(64-bit), Vista(64-bit), 7(64-bit), 8(64-bit), 8.1(64-bit), 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It adds the following processes:

  • "{Malware filepath}\{Malware filename}" /_ShowProgress

Download Routine

This Potentially Unwanted Application accesses the following websites to download files:

  • http://static.{BLOCKED}s-online.com/exe/PDFCreator.exe

As of this writing, the said sites are inaccessible.

Other Details

This Potentially Unwanted Application connects to the following website to send and receive information:

  • http://ww1.{BLOCKED}smiles.com/
  • http://d.{BLOCKED}d.com/widget/render/hash/84d4baf304e47282405d6a04e2a11e84
  • http://os2.{BLOCKED}converter.com/Aff-AD/?v=3.0&c=682270375
  • http://rp.{BLOCKED}-converter.com/?pcrc=437349436
  • http://www.{BLOCKED}-converter.com/pdf-creator/welcome/oc/?&adnm=36081343018&i=s&grid=&lg=ja&cc=JP&clg=&c=1&d=0&cid=_850487851&kw=pdf&mt=&mn=template.k-solution.info&ct=&nt=D&expr=&ap=none&dv=c&agid=_{UID}&gclid=CNmck_-wwb0CFcwipQodgWIA_g&iv=0
  • http://ww1.{BLOCKED}-converter.com/?subid1={UID}
  • http://ww1.{BLOCKED}converter.com/track.php?domain=thefreepdf-converter.com&toggle=browserjs&uid=MTYwMjUxMjY0Ni4xOTI0OmQ4MGEyYmU5MWU0NDhlMDA5YWNjOTU5ODc2N2E5ZDJiY2RlNGZlMjM5Mjg4ZjMwYzJkOGYxNDFlOWViYWUyNTM6NWY4NDY3MDYyZWY2Yg%3D%3D
  • http://{BLOCKED}ch.com/?dn=thefreepdf-converter.com&pid={UID}

It displays the following images:

  SOLUTION

Minimum Scan Engine: 9.800
SSAPI PATTERN File: 2.342.00
SSAPI PATTERN Date: 08 Oct 2020

Step 1

Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.

Step 2

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 3

Search and delete this file

[ Learn More ]
There may be some files 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%\is{random characters}\css\ie6_main.css
  • %User Temp%\is{random characters}\css\main.css
  • %User Temp%\is{random characters}\css\sdk-ui\browse.css
  • %User Temp%\is{random characters}\css\sdk-ui\button.css
  • %User Temp%\is{random characters}\css\sdk-ui\checkbox.css
  • %User Temp%\is{random characters}\css\sdk-ui\images\button-bg.png
  • %User Temp%\is{random characters}\css\sdk-ui\images\progress-bg-corner.png
  • %User Temp%\is{random characters}\css\sdk-ui\images\progress-bg.png
  • %User Temp%\is{random characters}\css\sdk-ui\images\progress-bg2.png
  • %User Temp%\is{random characters}\css\sdk-ui\progress-bar.css
  • %User Temp%\is{random characters}\csshover3.htc
  • %User Temp%\is{random characters}\dat\upd.DAT
  • %User Temp%\is{random characters}\form.bmp.Mask
  • %User Temp%\is{random characters}\images\BG.png
  • %User Temp%\is{random characters}\images\Close.png
  • %User Temp%\is{random characters}\images\Close_Hover.png
  • %User Temp%\is{random characters}\images\Color_Button.png
  • %User Temp%\is{random characters}\images\Color_Button_Hover.png
  • %User Temp%\is{random characters}\images\Grey_Button.png
  • %User Temp%\is{random characters}\images\Grey_Button_Hover.png
  • %User Temp%\is{random characters}\images\Loader.gif
  • %User Temp%\is{random characters}\images\Logo.png
  • %User Temp%\is{random characters}\images\Progress.png
  • %User Temp%\is{random characters}\images\ProgressBar.png
  • %User Temp%\is{random characters}\images\text-bg.png
  • %User Temp%\is{random characters}\locale\DE.locale
  • %User Temp%\is{random characters}\locale\EN.locale
  • %User Temp%\is{random characters}\locale\ES.locale
  • %User Temp%\is{random characters}\locale\FR.locale
  • %User Temp%\is{random characters}\locale\IT.locale
  • %User Temp%\is{random characters}\locale\PL.locale
  • %User Temp%\is{random characters}\locale\PT.locale
  • %User Temp%\is{random characters}\locale\RU.locale
  • %User Temp%\is{random characters}\locale\UA.locale
  • %User Temp%\is{random characters}\bootstrap_34102.html
  • %User Temp%\{random characters}.log
  • %User Temp%\ICReinstall_{grayware filename}.exe
  • %User Temp%\is1242154493\2042623_stp.EXE
  • %User Temp%\is1242154493\2042623_stp.EXE.part
  • %Desktop%\Continue Pdf Creator Installation.lnk
  • %Program Files%\is{random characters}.log

Step 4

Scan your computer with your Trend Micro product to delete files detected as PUA.Win32.Installcore.USMANHOBUV. 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 the following Trend Micro Support pages for more information:


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