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MITRE ATT&CK  /  T1557.001

T1557.001

Name Resolution Poisoning and SMB Relay

SUB-TECHNIQUE Credential Access Collection

Description

By responding to LLMNR/NBT-NS/mDNS network traffic, adversaries may spoof an authoritative source for name resolution to force communication with an adversary controlled system.(Citation: BlackCat ransomware) This activity may be used to collect or relay authentication materials.Link-Local Multicast Name Resolution (LLMNR) and NetBIOS Name Service (NBT-NS) are Microsoft Windows components that serve as alternate methods of host identification. LLMNR is based upon the Domain Name System (DNS) format and allows hosts on the same local link to perform name resolution for other hosts. NBT-NS identifies systems on a local network by their NetBIOS name.(Citation: Wikipedia LLMNR)(Citation: TechNet NetBIOS)Multicast Domain Name System(mDNS) is a zero-configuration service used to resolve hostnames to IP addresses with “.local” as a top-level domain. MDNS is based upon Domain Name System (DNS) format and allows hosts on the same network segment to perform name resolution for other hosts, using multicast.(Citation: mDNS RFC)Adversaries can spoof an authoritative source for name resolution on a victim network by responding to LLMNR (UDP 5355)/NBT-NS (UDP 137)/mDNS (UDP 5353) traffic as if they know the identity of the requested host, effectively poisoning the service so that the victims will communicate with the adversary controlled system. If the requested host belongs to a resource that requires identification/authentication, the username and NTLMv2 hash will then be sent to t…

Platforms

Windows

Mitigations

  • M1042 — Disable or Remove Feature or Program
  • M1031 — Network Intrusion Prevention
  • M1030 — Network Segmentation
  • M1037 — Filter Network Traffic
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Source: MITRE ATT&CK Enterprise matrix. View on attack.mitre.org →

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