BKDR_BRAMBUL.TPR

October 01, 2014
 Analysis by: Jaime Benigno Reyes
 ALIASES:

Backdoor:Win32/Brambul.A (Microsoft)

 PLATFORM:

Windows

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

  • Threat Type: Backdoor

  • Destructiveness: No

  • Encrypted:

  • 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.

  TECHNICAL DETAILS

File Size:

18,977 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

28 Feb 2013

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.

Other System Modifications

This backdoor adds the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SharedAccess\Parameters\
FirewallPolicy\FirewallRules
TCP Query User{random}{malware path}\{malware name} = "v2.10|Action=Allow|Active=TRUE|Dir=In|Protocol=6|Profile=Public|App={malware path}\{malware name}|Name={malware base name}|Desc={malware base name}|Defer=User|"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\SharedAccess\Parameters\
FirewallPolicy\FirewallRules
UDP Query User{random}{malware path}\{malware name} = "v2.10|Action=Allow|Active=TRUE|Dir=In|Protocol=17|Profile=Public|App={malware path}\{malware name}|Name={malware base name}|Desc={malware base name}|Defer=User|"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
{malware path}\{malware name} = "{malware path}\{malware name}:*:Enabled:{malware base name}"