RANSOM_HPCRYPTESLA.SM1

March 23, 2016
 Analysis by: Pearl Charlaine Espejo
 ALIASES:

Ransom.TeslaCrypt (Malwarebytes); Trojan-Ransom.TeslaCrypt (Ikarus); W32/Filecoder_TeslaCrypt.I!tr (Fortinet); Win32/Filecoder.TeslaCrypt.I (ESET-NOD32)

 PLATFORM:

Windows

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Downloaded from the Internet

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.

It does not have any propagation routine.

It does not have any backdoor routine.

It modifies the Internet Explorer Zone Settings.

It connects to certain websites to send and receive information. This is the Trend Micro detection for files that exhibit certain behaviors. It deletes itself after execution. It gathers information and reports it to its servers.

  TECHNICAL DETAILS

File Size:

344,064 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

16 Mar 2016

Payload:

Connects to URLs/IPs, Displays message, Encrypts files, Drops files

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 and executes them:

  • %User Profile%\Documents\{random filename}.exe (with non-Administrator Privileges)
  • %Windows%\{random filename}.exe (with Administrator Privileges)

(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.. %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.)

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

  • 345432-123rvr4

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
{random} = "%System%\cmd.exe /c start "" "%Windows%\{random filename}.exe"" (Note: with Administrator Privileges)

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random} = "%System%\cmd.exe /c start "" "%User Profile%\Documents\{random filename}.exe "" (Note: with non-Administrator Privileges)

Other System Modifications

This Trojan adds the following registry keys:

HKEY_CURRENT_USER\Software\zzzsys

HKEY_CURRENT_USER\Software\{Installation ID}

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Policies\
System
EnabledLinkConnections = "1"

HKEY_CURRENT_USER\Software\{Installation ID}
data = {encryption information}

HKEY_CURRENT_USER\Software\zzzsys
ID = {Installation ID}

Propagation

This Trojan does not have any propagation routine.

Backdoor Routine

This Trojan does not have any backdoor routine.

Web Browser Home Page and Search Page Modification

This Trojan modifies the Internet Explorer Zone Settings.

Dropping Routine

This Trojan drops the following files:

  • %User Profile%\Documents\recover_file_{random letters}.txt
  • %Desktop%\_ReCoVeRy_.TXT
  • %Desktop%\_ReCoVeRy_.HTM
  • %Desktop%\_ReCoVeRy_.png
  • {folders containing encrypted files}\_ReCoVeRy_+{random letters}.png
  • {folders containing encrypted files}\_ReCoVeRy_+{random letters}.txt
  • {folders containing encrypted files}\_ReCoVeRy_+{random letters}.html

(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.. %Desktop% is the desktop folder, where it usually is C:\Documents and Settings\{user name}\Desktop in Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\Desktop in 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 Trojan connects to the following website to send and receive information:

  • http://{BLOCKED}tecnicos.com/media/editors/wstr.php
  • http://{BLOCKED}ctivo.com/wstr.php
  • http:/{BLOCKED}rnal.com/pmtsys/fonts/wstr.php
  • http://{BLOCKED}yeli.com/wstr.php
  • http://{BLOCKED}online.com/wstr.php
  • http://{BLOCKED}turemediablog.com/wp-includes/fonts/wstr.php

It encrypts files with the following extensions:

  • .3fr
  • .7z
  • .accdb
  • .ai
  • .amp
  • .apk
  • .arch00
  • .arw
  • .asset
  • .avi
  • .bar
  • .bay
  • .bc6
  • .bc7
  • .big
  • .bik
  • .bkf
  • .bkp
  • .blob
  • .bsa
  • .cas
  • .cdr
  • .cer
  • .cfr
  • .cr2
  • .crt
  • .crw
  • .css
  • .csv
  • .d3dbsp
  • .das
  • .dazip
  • .db0
  • .dba
  • .dbf
  • .dcr
  • .der
  • .desc
  • .dmp
  • .dng
  • .doc
  • .docm
  • .docx
  • .dwg
  • .dxg
  • .epk
  • .eps
  • .erf
  • .esm
  • .ff
  • .flv
  • .forge
  • .fos
  • .fpk
  • .fsh
  • .gdb
  • .gho
  • .hkdb
  • .hkx
  • .hplg
  • .hvpl
  • .ibank
  • .icxs
  • .indd
  • .itd
  • .itdb
  • .itl
  • .itm
  • .iwd
  • .iwi
  • .jpeg
  • .jpg
  • .js
  • .kdb
  • .kdc
  • .kf
  • .layout
  • .lbf
  • .litemod
  • .lrf
  • .ltx
  • .lvl
  • .m2
  • .m3u
  • .m4a
  • .mcmeta
  • .mdb
  • .mdbackup
  • .mdd
  • .mddata
  • .mdf
  • .mef
  • .menu
  • .mlx
  • .mov
  • .mp4
  • .mpqge
  • .mrwref
  • .ncf
  • .nrw
  • .ntl
  • .odb
  • .odc
  • .odm
  • .odp
  • .ods
  • .odt
  • .orf
  • .p12
  • .p7b
  • .p7c
  • .pak
  • .pdd
  • .pdf
  • .pef
  • .pem
  • .pfx
  • .pkb
  • .pkpass
  • .png
  • .ppt
  • .pptm
  • .pptx
  • .psd
  • .psk
  • .pst
  • .ptx
  • .py
  • .qdf
  • .qic
  • .r3d
  • .raf
  • .rar
  • .raw
  • .rb
  • .re4
  • .rgss3a
  • .rim
  • .rofl
  • .rtf
  • .rw2
  • .rwl
  • .sav
  • .sb
  • .sid
  • .sidd
  • .sidn
  • .sie
  • .sis
  • .slm
  • .snx
  • .sql
  • .sr2
  • .srf
  • .srw
  • .sum
  • .svg
  • .syncdb
  • .t12
  • .t13
  • .tax
  • .tor
  • .txt
  • .upk
  • .vcf
  • .vdf
  • .vfs
  • .vfs0
  • .vpk
  • .vpp_pc
  • .vtf
  • .w3x
  • .wallet
  • .wb2
  • .wma
  • .wmo
  • .wmv
  • .wotreplay
  • .wpd
  • .wps
  • .x3f
  • .xf
  • .xlk
  • .xls
  • .xlsb
  • .xlsm
  • .xlsx
  • .xxx
  • .zip
  • .ztm
  • .ztmp

This is the Trend Micro detection for:

It deletes itself after execution.

It gathers the following information and reports it to its servers:

  • Infection status
  • Bitcoin address
  • Total size of encrypted files
  • Malware version
  • OS information
  • Installation ID

NOTES:

It deletes shadow copies by executing the following command:

  • WMIC.exe shadowcopy delete/nointeractive

It terminates processes containing the following strings:

  • askmg
  • rocex
  • egedi
  • sconfi
  • cmd

It appends the extension .MP3 to the filename of the encrypted files.

It avoids encrypting files from the following directories:

  • Windows
  • Program Files
  • %All Users Profile%\Application Data (Windows XP and below)
  • ProgramData (Windows Vista and above)

It avoids encrypting files with the following strings:

  • recove
  • .mp3

It encrypts files in all fixed, removable, and network drives and shares.

It opens the following ransom notes after encryption:

It does not have rootkit capabilities.

It does not exploit any vulnerability.

  SOLUTION

Minimum Scan Engine:

9.800

FIRST VSAPI PATTERN FILE:

12.404.06

FIRST VSAPI PATTERN DATE:

15 Mar 2016

VSAPI OPR PATTERN File:

12.405.00

VSAPI OPR PATTERN Date:

15 Mar 2016

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

Identify and terminate files detected as RANSOM_HPCRYPTESLA.SM1

[ Learn More ]
  1. Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

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
    • {random} = "%System%\cmd.exe /c start "" "%Windows%\{random filename}.exe""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\system
    • EnableLinkedConnections = "1"

Step 5

Delete this registry key

[ 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
    • zzzsys
  • In HKEY_CURRENT_USER\Software
    • {Installation ID}

Step 6

Search and delete these files

[ 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 Profile%\Documents\recover_file_{random letters}.txt
  • %Desktop%\_ReCoVeRy_.TXT
  • %Desktop%\_ReCoVeRy_.HTM
  • %Desktop%\_ReCoVeRy_.png
  • _ReCoVeRy_+{random letters}.png
  • _ReCoVeRy_+{random letters}.txt
  • _ReCoVeRy_+{random letters}.html

Step 7

Reset Internet security settings

[ Learn More ]

Step 8

Scan your computer with your Trend Micro product to delete files detected as RANSOM_HPCRYPTESLA.SM1. 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

Restore encrypted files from backup.


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