RANSOM_WOOLY.A
MSIL.Trojan-Ransom.WoolyBear.A (GData); Trojan.Ransom.Wooly (ALYac)
Windows

Threat Type: Ransomware
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
This Ransomware arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It is capable of encrypting files in the affected system.
It encrypts files with specific file extensions. It encrypts files found in specific folders.
TECHNICAL DETAILS
Arrival Details
This Ransomware 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 Ransomware drops the following files:
- %Application Data%\Internet Browser\libeay32.dll
- %Application Data%\Internet Browser\libevent-2-0-5.dll
- %Application Data%\Internet Browser\libevent_core-2-0-5.dll
- %Application Data%\Internet Browser\libevent_extra-2-0-5.dll
- %Application Data%\Internet Browser\libgcc_s_sjlj-1.dll
- %Application Data%\Internet Browser\libssp-0.dll
- %Application Data%\Internet Browser\ssleay32.dll
- %Application Data%\Internet Browser\tor-gencert.exe
- %Application Data%\Internet Browser\zlib1.dll
- %Application Data%\Keys\0000000000000.woolybear
- %Application Data%\Keys\1111111111111.woolybear
(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.)
It drops and executes the following files:
- %Application Data%\Internet Browser\tor.exe
(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 Ransomware is capable of encrypting files in the affected system.
Ransomware Routine
This Ransomware encrypts files with the following extensions:
- .doc
- .docx
- .xls
- .xlsx
- .ppt
- .pptx
- .pst
- .ost
- .msg
- .eml
- .vsd
- .vsdx
- .txt
- .csv
- .rtf
- .123
- .wks
- .wk1
- .dwg
- .onetoc2
- .snt
- .jpeg
- .jpg
- .docb
- .docm
- .dot
- .dotm
- .dotx
- .xlsm
- .xlsb
- .xlw
- .xlt
- .xlm
- .xlc
- .xltx
- .xltm
- .pptm
- .pot
- .pps
- .ppsm
- .ppsx
- .ppam
- .potx
- .potm
- .edb
- .hwp
- .602
- .sxi
- .sti
- .sldx
- .sldm
- .sldm
- .vdi
- .vmdk
- .vmx
- .gpg
- .aes
- .ARC
- .PAQ
- .bz2
- .tbk
- .bak
- .tar
- .tgz
- .gz
- .7z
- .rar
- .zip
- .backup
- .iso
- .vcd
- .bmp
- .png
- .gif
- .raw
- .cgm
- .tif
- .tiff
- .nef
- .psd
- .ai
- .svg
- .djvu
- .m4u
- .m3u
- .mid
- .wma
- .flv
- .3g2
- .mkv
- .3gp
- .mp4
- .mov
- .avi
- .asf
- .mpeg
- .vob
- .mpg
- .wmv
- .fla
- .swf
- .wav
- .mp3
- .sh
- .class
- .blend
- .jar
- .java
- .rb
- .asp
- .php
- .jsp
- .brd
- .sch
- .dch
- .dip
- .pl
- .vb
- .vbs
- .ps1
- .bat
- .cmd
- .js
- .asm
- .h
- .pas
- .cpp
- .c
- .cs
- .suo
- .sln
- .ldf
- .mdf
- .ibd
- .myi
- .myd
- .frm
- .odb
- .dbf
- .db
- .mdb
- .accdb
- .sql
- .sqlitedb
- .sqlite3
- .asc
- .lay6
- .lay
- .mml
- .sxm
- .otg
- .odg
- .uop
- .std
- .sxd
- .otp
- .odp
- .wb2
- .slk
- .dif
- .stc
- .sxc
- .ots
- .ods
- .3dm
- .max
- .3ds
- .uot
- .stw
- .sxw
- .ott
- .odt
- .pem
- .p12
- .csr
- .crt
- .key
- .pfx
- .der
It encrypts files found in the following folders:
- %User Profile%
(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 appends the following extension to the file name of the encrypted files:
- .wooly
SOLUTION
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
Step 4
Search and delete this file
- %Application Data%\Internet Browser\libeay32.dll
- %Application Data%\Internet Browser\libevent-2-0-5.dll
- %Application Data%\Internet Browser\libevent_core-2-0-5.dll
- %Application Data%\Internet Browser\libevent_extra-2-0-5.dll
- %Application Data%\Internet Browser\libgcc_s_sjlj-1.dll
- %Application Data%\Internet Browser\libssp-0.dll
- %Application Data%\Internet Browser\ssleay32.dll
- %Application Data%\Internet Browser\tor-gencert.exe
- %Application Data%\Internet Browser\zlib1.dll
- %Application Data%\Keys\0000000000000.woolybear
- %Application Data%\Keys\1111111111111.woolybear
- %Application Data%\Internet Browser\tor.exe
Step 5
Restart in normal mode and scan your computer with your Trend Micro product for files detected as RANSOM_WOOLY.A. 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 6
Restore encrypted files from backup.
Did this description help? Tell us how we did.