Ransom_CRYPHYDRA.F117AC

March 01, 2017
 ALIASES:

Ransom:Win32/HydraCrypt.A (Microsoft); Ransom-FBX!C7221DEF290A (McAfee); Trojan.Gen.2 (Symantec); HEUR:Trojan.Win32.Generic (Kaspersky); Troj/Ransom-EDA (Sophos); BehavesLike.Win32.Malware.rwx (mx-v) (Sunbelt); Trojan horse Ransom_r.BOV (AVG)

 PLATFORM:

Windows

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW

This Trojan 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

File Size:

99,328 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

01 Mar 2017

Arrival Details

This Trojan 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 Trojan drops the following copies of itself into the affected system:

  • %User Profile%\Application Data\Spy Security SoftWare_cc58263a_68ad0fd0.exe
  • A:\Microsoft Decryptor Ransomware.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.)

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Spy Security SoftWare = "{malware path and file name} "

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\RunOnce
*Spy Security SoftWare = "{malware path and file name} "

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Spy Security SoftWares = "{random characters}"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\RunOnce
*Spy Security SoftWares = "{random characters}"

Other System Modifications

This Trojan deletes the following files:

  • {malware path and file name}:zone.identifier
  • %User Profile%\Application Data\Spy Security SoftWare_cc58263a_68ad0fd0.exe:Zone.Identifier
  • A:\Microsoft Decryptor Ransomware.exe:Zone.Identifier

(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 registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\Shell
Spy Security SoftWareTEMP = "{malware path and file name}"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\Shell
Nodes Slots = "{random values}"

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}39.53/{random path}?{random characters}
  • {BLOCKED}28.61
  • {BLOCKED}7.5.110
  • {BLOCKED}.253.109

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.8

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

Restart in Safe Mode

[ Learn More ]

Step 3

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
    • Spy Security SoftWare = "{malware path and file name} "
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce
    • *Spy Security SoftWare = "{malware path and file name} "
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • Spy Security SoftWares = "{random characters}"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce
    • *Spy Security SoftWares = "{random characters}"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\Shell
    • Spy Security SoftWareTEMP = "{malware path and file name}"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\Shell
    • Nodes Slots = "{random values}"

Step 4

Restart in normal mode and scan your computer with your Trend Micro product for files detected as Ransom_CRYPHYDRA.F117AC. 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 5

Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.

  • {malware path and file name}:zone.identifier
  • %User Profile%\Application Data\Spy Security SoftWare_cc58263a_68ad0fd0.exe:Zone.Identifier
  • A:\Microsoft Decryptor Ransomware.exe:Zone.Identifier


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