Network Service Discovery T1046
Adversaries may attempt to get a listing of services running on remote hosts and local network infrastructure devices, including those that may be vulnerable to remote software exploitation. Common methods to acquire this information include port, vulnerability, and/or wordlist scans using tools that are brought onto a system.
Events covered
14 catalog events are tagged with this technique by at least one rule.
Authoring guide
Patterns shared across the 31 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 (28 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 (145 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 (27 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 14 rules
- Advanced IP Scanner - File Event
- Anonymous access performed to multiple targets
- Grixba Malware Reconnaissance Activity
- HackTool - winPEAS Execution
- HackTool - WinPwn Execution
- HackTool - WinPwn Execution - ScriptBlock
- Network login performed to multiple targets
- PUA - Advanced IP Scanner Execution
- PUA - Advanced Port Scanner Execution
- PUA - NimScan Execution
- PUA - Nmap/Zenmap Execution
- PUA - SoftPerfect Netscan Execution
- Python Initiated Connection
- Suspicious anonymous login (domain specified)
Splunk 14 rules
- Advanced IP or Port Scanner Execution
- Advanced IP Scanner Execution (Sysmon)
- Advanced IP Scanner Execution (Windows Event Log)
- Advanced Port Scanner Execution (Sysmon)
- Advanced Port Scanner Execution (Windows Event Log)
- FScan.exe Network Scan (Sysmon)
- FScan.exe Network Scan (Windows Event Log)
- Internal Port Scan - Critical Ports (Windows Event Log)
- masscan Execution - Windows (PowerShell)
- masscan Execution - Windows (Sysmon)
- masscan Execution - Windows (Windows Event Log)
- SoftPerfect Network Scanner Execution (Sysmon)
- SoftPerfect Network Scanner Execution (Windows Event Log)
- Windows PsTools Recon Usage