arrow_back
search
close

WORM_PHORPIEX.D

July 12, 2016
 Analysis by: Jennifer Gumban
 ALIASES:

Worm:Win32/Phorpiex.P (Microsoft)

 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Propagates via removable drives, Downloaded from the Internet


This worm arrives via removable drives. It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

It joins an Internet Relay Chat (IRC) channel.

It connects to certain websites to send and receive information. However, as of this writing, the said sites are inaccessible.

  TECHNICAL DETAILS

File Size:

84,992 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

11 Jul 2016

Payload:

Compromises system security, Connects to URLs/IPs

Arrival Details

This worm arrives via removable drives.

It 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 worm adds the following folders:

  • %User Profile%\P-7-78-8964-9648-3874
  • {Removable Drive}:\69482745

(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.)

It drops the following copies of itself into the affected system and executes them:

  • %User Profile%\P-7-78-8964-9648-3874\wincrs.exe

(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.)

It adds the following mutexes to ensure that only one of its copies runs at any one time:

  • 0hai

Autostart Technique

This worm adds the following registry entries to enable its automatic execution at every system startup:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Microsoft Windows System = "%User Profile%\P-7-78-8964-9648-3874\wincrs.exe"

Other System Modifications

This worm creates the following registry entry(ies) to bypass Windows Firewall:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
wincrs.exe = "%User Profile%\P-7-78-8964-9648-3874\wincrs.exe:*:Enabled:Microsoft Windows System"

Propagation

This worm drops the following copy(ies) of itself in all removable drives:

  • {Removable Drive}:\wincrs.exe
  • {Removable Drive}:\69482745\{Folder Names}.exe

It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

The said .INF file contains the following strings:

[autorun]
icon=%SystemRoot%\system32\SHELL32.dll,4
action=Open folder to view files
shellexecute=wincrs.exe
UseAutoPlay=1

Backdoor Routine

This worm joins any of the following Internet Relay Chat (IRC) channels:

  • #32769
  • #32772
  • #32774
  • #32770

It accesses a remote Internet Relay Chat (IRC) server where it receives the following commands from a remote malicious user:

  • Download and execute arbitrary files
  • Join other IRC channel
  • Uninstall itself

Download Routine

This worm saves the files it downloads using the following names:

  • %Application Data%\msnsvconfig.txt

(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.)

Other Details

This worm connects to the following website to send and receive information:

  • phx.{BLOCKED}num.net

However, as of this writing, the said sites are inaccessible.

NOTES:

This worm creates .LNK (shortcut) files pointing to the copy of this worm named {Removable Drive}:\69482745\{Folder Names}.exe. The variable {Folder Names} are the folder names found at the root of the removable drive, if there are any.

It then sets the attribute of the said folders to Hidden.

The message can be of different language depending on the locale and system language of the affected machine. English:

  • tell me what you think of this picture i edited
  • this is the funniest photo ever!
  • tell me what you think of this photo i don't think i will ever sleep again after seeing this photo
  • i cant believe i still have this picture should i make this my default picture?

      It checks the presence of the following to see if its running in a virtual machine:

      • qemu
      • virtual
      • vmware
      • SbieDllX.dll
      • SbieDll.dll

  SOLUTION

Minimum Scan Engine:

9.800

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

Restart in Safe Mode

[ Learn More ]

Step 4

Delete this registry value

[ Learn More ]

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
    • Microsoft Windows System = "%User Profile%\P-7-78-8964-9648-3874\wincrs.exe"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\services\SharedAccess\Parameters\FirewallPolicy\StandardProfile\AuthorizedApplications\List\%User Profile%\P-7-78-8964-9648-3874
    • wincrs.exe = "%User Profile%\P-7-78-8964-9648-3874\wincrs.exe:*:Enabled:Microsoft Windows System"

Step 5

Search and delete these folders

[ 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 Profile%\M-1-25-8784-4125-7572
  • {Removable Drive}:\69482745

Step 6

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.
  • %Application Data%\msnsvconfig.txt

Step 7

Search and delete AUTORUN.INF files created by WORM_PHORPIEX.D that contain these strings

[ Learn More ]
[autorun]
icon=%SystemRoot%\system32\SHELL32.dll,4
action=Open folder to view files
shellexecute=wincsa.exe
UseAutoPlay=1

Step 8

Restart in normal mode and scan your computer with your Trend Micro product for files detected as WORM_PHORPIEX.D. 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.

Step 9

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

NOTES:

Delete all the created {Folder Names}.LNK files in the removable drives.


Did this description help? Tell us how we did.