Analysis by: Ryan Paolo Maglaque

 PLATFORM:

Windows

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

  • Threat Type: Rootkit

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Canal de infecção: Dropped by other malware, Downloaded from the Internet

This Rootkit 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

Tipo de compactação: 57,040 bytes
Tipo de arquivo: SYS
Residente na memória: Yes
Data de recebimento das amostras iniciais: 08 Jun 2017
Carga útil: Others

Arrival Details

This Rootkit arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Other Details

This Rootkit does the following:

  • Adds filter on tcp/ip based networks
  • It uses RtlGetVersion to check os version
  • Hooks the following IRP major functions:
    • IRP_MJ_CREATE
    • IRP_MJ_CLOSE
    • IRP_MJ_READ
    • IRP_MJ_WRITE
    • IRP_MJ_SHUTDOWN
    • IRP_MJ_DEVICE_CONTROL
  • It disables kernel debugger
  • If the system is older than windows Vista, it will hook the following tcpip.sys functions:
    • IpInjectPkt
    • IpAllocBuff
    • IpFreeBuff
  • If the system is windows Vista or greater, it will hook the following ndis.sys and fwpkclnt.sys functions:
    • NdisAllocateMdl
    • NdisAllocateMemoryWithTagPriority
    • NdisFreeMdl
    • NdisRetreatNetBufferDataStart
    • NdisGetDataBuffer
    • NdisFreeNetBufferListPool
    • NdisFreeGenericObject
    • NdisAllocateNetBufferListPool
    • NdisAllocateGenericObject
    • NdisAdvanceNetBufferDataStart
    • FwpsInjectionHandleCreate0
    • FwpsInjectNetworkSendAsync0
    • FwpsInjectNetworkReceiveAsync0
    • FwpsQueryPacketInjectionState0
    • FwpsInjectionHandleDestroy0
    • FwpsCalloutRegister0
    • FwpsCalloutUnregisterByKey0
    • FwpmEngineOpen0
    • FwpmEngineClose0
    • FwpmTransactionBegin0
    • FwpmTransactionAbort0
    • FwpmTransactionCommit0
    • FwpmCalloutAdd0
    • FwpmCalloutDeleteByKey0
    • FwpmFilterAdd0
    • FwpmSubLayerAdd0
    • FwpmFilterDeleteByKey0
    • FwpmSubLayerDeleteByKey0
    • FwpsAllocateNetBufferAndNetBufferList0
    • FwpsFreeNetBufferList0
    • FwpsFreeCloneNetBufferList0
  • It creates the following callout filters:
    • CalloutIn
    • CalloutOut
    • CalloutListen
    • CalloutAccept
    • CalloutResource

  SOLUTION

Mecanismo de varredura mínima: 9.850
Primeiro arquivo padrão VSAPI: 13.570.04
Data do lançamento do primeiro padrão VSAPI: 02 Aug 2017
VSAPI OPR Pattern Version: 13.571.00
VSAPI OPR Pattern veröffentlicht am: 03 Aug 2017

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

Scan your computer with your Trend Micro product to delete files detected as RTKT64_KERLISEN.B. 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.


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