System Network Configuration Discovery T1016

Events covered

13 catalog events are tagged with this technique by at least one rule.

Authoring guide

Patterns shared across the 70 rules above: which fields they filter on, what specific values they look for, and what they exclude. The catalog normalizes field names across vendors so Sigma's Image, Elastic's process.name, and Splunk's process_name collapse into one row. Each rule contributes at most once per row.

Fields filtered most (61 distinct)

The fields most rules look at when detecting this technique. The How column shows the operators authors use (eq, wildcard, regex_match, match) and how often each appears. Sample values are concrete examples to start from, not an exhaustive list.

Top indicator values (930 distinct)

Specific (field, operator, value) combinations the rules check for, ranked by how many rules under this technique use each one. The Corpus reach column counts how many rules across the entire catalog (any technique) check the same combination. High numbers point to widely-used indicators that are likely noisy on their own; combine them with another condition for useful signal. Blank means the combination is specific to rules under this technique. Click a value to expand the rules under this technique that use it.

Exclusions (221 distinct)

Field/operator/value combinations excluded by rules under this technique (top-level not() clauses), sorted by how many rules exclude each. These are the false-positive paths the community has learned to filter out. A new rule that ignores the high-count entries here will likely fire on the same noisy paths. Click a value to expand the rules under this technique that exclude it.

Rules under this technique

Every rule in the catalog tagged with this technique, grouped by vendor. Click a rule title for its full predicates, exclusions, and indicators.

Sigma 16 rules

• Cisco Discovery
• Failed DNS server zone transfer for enumeration purposes
• Firewall Configuration Discovery Via Netsh.EXE
• Firewall configuration enumerated (command)
• Firewall configuration enumerated (PowerShell)
• Local Firewall Rules Enumeration Via NetFirewallRule Cmdlet
• Nltest.EXE Execution
• OpenCanary - SNMP OID Request
• Potential Pikabot Discovery Activity
• Potential Recon Activity Via Nltest.EXE
• Scheduled task enumerated
• Suspicious Network Command
• Suspicious Network Connection to IP Lookup Service APIs
• System Network Discovery - Linux
• System Network Discovery - macOS
• Winlogon process contact to C2 - Blacklotus (Sysmon)

Elastic 26 rules

• Active Directory Discovery using AdExplorer
• AdFind Command Activity
• Deprecated - PowerShell Script with Discovery Capabilities
• Discovery Command Output Written to Suspicious File
• Discovery of Internet Capabilities via Built-in Tools
• DNS Enumeration Detected via Defend for Containers
• DNS Request for IP Lookup Service via Unsigned Binary
• Enumeration Command Spawned via WMIPrvSE
• External IP Address Discovery via Curl
• External IP Lookup from Non-Browser Process
• Potential Meterpreter Reverse Shell
• PowerShell Suspicious Discovery Related Windows API Functions
• Remote System Discovery Commands
• Suspicious Instance Metadata Service (IMDS) API Command Line Execution
• Suspicious Instance Metadata Service (IMDS) API Request
• Suspicious JetBrains TeamCity Child Process
• Suspicious MS Office Child Process
• Suspicious PDF Reader Child Process
• Suspicious System Commands Executed by Previously Unknown Executable
• System and Network Configuration Check
• System Hosts File Access
• System Network Connections Discovery
• System Public IP Discovery via DNS Query
• Unusual Linux Network Configuration Discovery
• Windows System Network Connections Discovery
• Wireless Credential Dumping using Netsh Command

Splunk 25 rules

• Adfind Commands (PowerShell)
• Adfind Commands (Sysmon)
• Adfind Commands (Windows Event Log)
• Adfind Execution (EDR)
• Adfind Execution (PowerShell)
• Adfind Execution (Sysmon)
• Adfind Execution (Windows Event Log)
• Cisco IOS XE Reconnaissance Command Activity
• Cisco NVM - Suspicious Network Connection to IP Lookup Service API
• Domain Controller Enumeration via nltest (PowerShell)
• Domain Controller Enumeration via nltest (Sysmon)
• Domain Controller Enumeration via nltest (Windows Event Log)
• Linux Auditd System Network Configuration Discovery
• Linux System Network Discovery
• MacOS List Firewall Rules
• Multiple nslookup commands (Sysmon)
• Multiple nslookup commands (Windows Event Log)
• Network Discovery Using Route Windows App
• Nslookup Execution (Windows Event Log)
• Potential System Network Configuration Discovery Activity
• Windows Common Abused Cmd Shell Risk Behavior
• Windows Post Exploitation Risk Behavior
• Windows PowerShell Invoke-RestMethod IP Information Collection
• Windows System Network Config Discovery Display DNS
• Windows WinPEAS PowerShell Script Execution

Kusto 2 rules

• Powershell Empire Cmdlets Executed in Command Line
• Probable AdFind Recon Tool Usage

YARA-L 1 rule

• Recon Environment Enumeration Network CISA Report