BKDR_ZEGOST.DAM
Backdoor:Win32/Zegost.B (Microsoft); Backdoor.Zegost (Malwarebytes);
Windows
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Backdoor
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It executes commands from a remote malicious user, effectively compromising the affected system.
TECHNICAL DETAILS
152844 bytes
Yes
05 Apr 2014
Arrival Details
This backdoor arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
Autostart Technique
This backdoor registers as a system service to ensure its automatic execution at every system startup by adding the following registry keys:
• HKEY_LOCAL_MACHINE\System\CurrentControlSet\
Services\DirectX jrq
Backdoor Routine
This backdoor executes the following commands from a remote malicious user:
- Remote shell
- Get arbitrary file content
- Keyboard log
- Get phonebook
- Get user accounts
- Establish remote desktop
NOTES:
This is the Trend Micro detection for damaged samples of BKDR_ZEGOST variants. These samples have coding errors that prevent them from properly executing their routines.
SOLUTION
9.750
11.924.05
17 Sep 2015
11.925.00
18 Sep 2015
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
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. Before you could do this, you must restart in Safe Mode. For instructions on how to do this, you may refer to this page If the preceding step requires you to restart in safe mode, you may proceed to edit the system registry.
- In HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services
- DirectX jrq
- DirectX jrq
Step 4
Scan your computer with your Trend Micro product to delete files detected as BKDR_ZEGOST.DAM. 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.
Did this description help? Tell us how we did.