Remote System Discovery T1018

Events covered

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

Authoring guide

Patterns shared across the 85 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 (53 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 (528 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 (39 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 18 rules

• Active Directory Computers Enumeration With Get-AdComputer
• Chopper Webshell Process Pattern
• Cisco Discovery
• DirectorySearcher Powershell Exploitation
• DNS hosts file accessed via network share
• HackTool - NetExec Execution
• Linux Remote System Discovery
• Macos Remote System Discovery
• Net.EXE Execution
• Nltest.EXE Execution
• Potential Unconstrained Delegation Discovery Via Get-ADComputer - ScriptBlock
• PUA - AdFind Suspicious Execution
• PUA - Adidnsdump Execution
• Renamed AdFind Execution
• Share And Session Enumeration Using Net.EXE
• Suspicious Scan Loop Network
• Webshell Detection With Command Line Keywords
• Webshell Hacking Activity Patterns

Elastic 14 rules

• Active Directory Discovery using AdExplorer
• AdFind Command Activity
• DNS Enumeration Detected via Defend for Containers
• Enumerating Domain Trusts via DSQUERY.EXE
• Enumerating Domain Trusts via NLTEST.EXE
• Enumeration Command Spawned via WMIPrvSE
• Potential Enumeration via Active Directory Web Service
• Potential Network Scan Executed From Host
• Potential Network Sweep Detected
• Potential Subnet Scanning Activity from Compromised Host
• Remote System Discovery Commands
• Spike in Firewall Denies
• System Hosts File Access
• Windows Network Enumeration

Splunk 43 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 Remote Access Probe Burst
• Cisco Secure Firewall - Blocked Connection
• Cisco Secure Firewall - Repeated Blocked Connections
• Domain Controller Discovery with Nltest
• Domain Controller Discovery with Wmic
• Domain Controller Enumeration via nltest (PowerShell)
• Domain Controller Enumeration via nltest (Sysmon)
• Domain Controller Enumeration via nltest (Windows Event Log)
• FScan.exe Network Scan (Sysmon)
• FScan.exe Network Scan (Windows Event Log)
• GetAdComputer with PowerShell
• GetAdComputer with PowerShell Script Block
• GetDomainComputer with PowerShell
• GetDomainComputer with PowerShell Script Block
• GetDomainController with PowerShell
• GetDomainController with PowerShell Script Block
• GetWmiObject Ds Computer with PowerShell
• GetWmiObject Ds Computer with PowerShell Script Block
• Multiple nslookup commands (Sysmon)
• Multiple nslookup commands (Windows Event Log)
• NMAP Execution (EDR)
• NMAP Execution (PowerShell)
• NMAP Execution (Windows Event Log)
• Potential Ping Sweep (Windows Event Log)
• PowerHuntShares Commands (PowerShell)
• PowerHuntShares Commands (Sysmon)
• PowerHuntShares Commands (Windows Event Log)
• Remote System Discovery with Adsisearcher
• Remote System Discovery with Dsquery
• Remote System Discovery with Wmic
• Windows AdFind Exe
• Windows Get-AdComputer Unconstrained Delegation Discovery
• Windows Netspy Network Scanner Execution
• Windows PowerView Constrained Delegation Discovery
• Windows PowerView Unconstrained Delegation Discovery
• Windows PsTools Recon Usage

Kusto 9 rules

• Claroty - Policy violation
• Claroty - Suspicious activity
• Claroty - Suspicious file transfer
• Claroty - Threat detected
• Hunt for ADWS requests from unknown devices
• LDAP reconnaissance via search filters
• Probable AdFind Recon Tool Usage
• Probable AdFind Recon Tool Usage (Normalized Process Events)
• SonicWall - Allowed SSH, Telnet, and RDP Connections

Panther 1 rule

• Azure Excessive IP and VM Discovery