Analysis by: RonJay Kristoffer Caragay
ALIASES:

AdInstaller.Firseria (AVG); Win32:Firseria-A [PUP] (Avast); Win32/FirseriaInstaller.C (ESET-NOD32); PUP.Optional.Firseria (Malwarebytes); Application.Bundler.Firseria (F-Secure); Application.Bundler.Firseria.A (MicroWorld-eScan); not-a-virus:Downloader.Win32.Firser.a (Kaspersky)

 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, Dropped by other malware

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.

It connects to certain websites to send and receive information.

  TECHNICAL DETAILS

File Size: 190,776 bytes
Memory Resident: No
Initial Samples Received Date: 26 Mar 2015
Payload: Connects to URLs/IPs

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 adds the following folders:

  • %User Temp%\ins{random}

(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 drops and executes the following files:

  • %User Temp%\ins{random}\ins{random}.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.)

Other Details

This potentially unwanted application connects to the following website to send and receive information:

  • http://api.{BLOCKED}loadmr.com/installer/{data}
  • http://api.{BLOCKED}nloadmr.com/s/ender.min.js
  • http://api.{BLOCKED}cdn.com/installer/{data}
  • http://api.{BLOCKED}dn.com/s/ender.min.js
  • http://{BLOCKED}am.nr-data.net:443
  • http://{BLOCKED}con-4.newrelic.com/{data}

NOTES:

This potentiall unwanted application displays its user interface, asking to update an application:

When users click on UPDATE it downloads a file from the URL http://{BLOCKED}clip.com/n/{data}/{Application's name}. The name of the file contains strings related to the application.

It automatically redirects to the following download sites:

    http://dl.{BLOCKED}desk.com/n/{data}/{Application's name}?secure={value} http://dl.{BLOCKED}gion.com/n/{data}/{Application's name}?secure={value}

  SOLUTION

Minimum Scan Engine: 9.750

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

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 folder

[ 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%\ins{random}

Step 4

Scan your computer with your Trend Micro product to delete files detected as PUA_FIRSERIA. 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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