TROJ_CRYPLOCK.V
Windows
Threat Type: Trojan
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
Downloaded from the Internet, Dropped by other malware
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 connects to certain websites to send and receive information. However, as of this writing, the said sites are inaccessible.
TECHNICAL DETAILS
418,816 bytes
EXE
Yes
04 Oct 2014
Encrypts files, Steals information
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:
- %All Users Profile%\Application Data\{random characters 2}\01000000
- %Windows%\{random characters 1}.exe
(Note: %All Users Profile% is the All Users or Common profile folder, which is C:\Documents and Settings\All Users in Windows 2000, XP, and Server 2003, and C:\ProgramData in Windows Vista and 7.. %Windows% is the Windows folder, which is usually C:\Windows.)
It adds the following processes:
- explorer.exe
It injects itself into the following processes as part of its memory residency routine:
- explorer.exe
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 characters 3} = "%Windows%\{random characters 1}.exe"
Other System Modifications
This Trojan adds the following registry keys:
HKEY_CURRENT_USER\Software\{random characters 4}
It adds the following registry entries:
HKEY_CURRENT_USER\Software\{random characters 4}
01000000 = "{binary copy of itself}"
HKEY_CURRENT_USER\Software\{random characters 4}
02000000 = "%Windows%\{random characters 1}.exe"
HKEY_CURRENT_USER\Software\{random characters 4}
00000000 = "{hex values}"
Information Theft
This Trojan gathers the following data:
- Machine GUID
- Computer name
Other Details
This Trojan connects to the following website to send and receive information:
- http://{BLOCKED}ofnigeria.net:443
However, as of this writing, the said sites are inaccessible.
NOTES:
This Trojan connects to the URL above to download the key used in encrypting the files.
It encrypts the following files and appends "encrypted" to them:
- 3ds
- 3fr
- 3pr
- 7z
- ab4
- ac2
- accdb
- accde
- accdr
- accdt
- acr
- adb
- agd1
- ai
- ait
- al
- apj
- arw
- asm
- asp
- awg
- backup
- backupdb
- bak
- bdb
- bgt
- bik
- bkp
- blend
- bpw
- cdf
- cdr
- cdr3
- cdr4
- cdr5
- cdr6
- cdrw
- cdx
- ce1
- ce2
- cer
- cfp
- cgm
- cib
- cls
- cmt
- cpi
- cpp
- cr2
- craw
- crt
- crw
- csh
- csl
- css
- csv
- dac
- db
- db-journal
- db3
- dbf
- dc2
- dcr
- dcs
- ddd
- ddoc
- ddrw
- der
- design
- dgc
- djvu
- dng
- doc
- docm
- docx
- dot
- dotm
- dotx
- drf
- drw
- dwg
- dxb
- erbsql
- erf
- exf
- fdb
- ffd
- fff
- fh
- fhd
- fpx
- fxg
- gray
- grey
- gry
- hbk
- hpp
- ibank
- ibd
- ibz
- idx
- iiq
- incpas
- jpeg
- jpg
- js
- kc2
- kdbx
- kdc
- kpdx
- lua
- mdb
- mdc
- mef
- mfw
- mmw
- moneywell
- mos
- mpg
- mrw
- myd
- ndd
- nef
- nop
- nrw
- ns2
- ns3
- ns4
- nsd
- nsf
- nsg
- nsh
- nwb
- nx1
- nx2
- nyf
- odb
- odf
- odg
- odm
- odp
- ods
- odt
- orf
- otg
- oth
- otp
- ots
- ott
- p12
- p7b
- p7c
- pat
- pcd
- pef
- pem
- pfx
- php
- pl
- pot
- potm
- potx
- ppam
- pps
- ppsm
- ppsx
- ppt
- pptm
- pptx
- ps
- psafe3
- psd
- ptx
- py
- ra2
- raf
- rar
- raw
- rdb
- rtf
- rw2
- rwl
- rwz
- s3db
- sas7bdat
- sav
- sd0
- sd1
- sda
- sdf
- sldm
- sldx
- sql
- sqlite
- sqlite3
- sqlitedb
- sr2
- srf
- srw
- st4
- st5
- st6
- st7
- st8
- stc
- std
- sti
- stw
- stx
- sxc
- sxd
- sxg
- sxi
- sxm
- sxw
- txt
- wb2
- x3f
- xla
- xlam
- xll
- xlm
- xls
- xlsb
- xlsm
- xlsx
- xlt
- xltm
- xltx
- xlw
- xml
- ycbcra
- zip
After successfully encrypting user's files, it drops the ransom note DECRYPT_INSTRUCTIONS.html.
SOLUTION
9.700
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
Scan your computer with your Trend Micro product and note files detected as TROJ_CRYPLOCK.V
Step 4
Restart in Safe Mode
Step 5
Delete this registry key
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
- {random characters 4}
- {random characters 4}
Step 6
Delete this registry value
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 characters 3} = "%Windows%\{random characters 1}.exe"
- {random characters 3} = "%Windows%\{random characters 1}.exe"
- In HKEY_CURRENT_USER\Software\{random characters 4}
- 01000000 = {binary copy of itself}
- 01000000 = {binary copy of itself}
- In HKEY_CURRENT_USER\Software\{random characters 4}
- 02000000 = %Windows%\{random characters 1}.exe
- 02000000 = %Windows%\{random characters 1}.exe
- In HKEY_CURRENT_USER\Software\{random characters 4}
- 00000000 = {hex values}
- 00000000 = {hex values}
Step 7
Search and delete these files
- DECRYPT_INSTRUCTIONS.html
Step 8
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_CRYPLOCK.V. 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
The following created files/folders/registry keys/registry entries cannot be identified by the user since there are no reference values in the created key. The only way it can be identified is by comparing the present system information with a backup. Note that the said components do not have to be deleted since it won't be harmful to the system.
- %All Users Profile%\Application Data\{random characters 2}\01000000
- %Windows%\{random characters 1}.exe
- HKEY_CURRENT_USER\Software\{random characters 4}
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