Detect Employee Names in CrowdStrike LogScale
Adversaries may gather employee names that can be used during targeting. Employee names can be used to derive email addresses as well as to help guide other reconnaissance efforts and craft more-believable lures. Adversaries may easily gather employee names since they may be readily available and exposed via online or other accessible data sets such as social media, LinkedIn, corporate websites, and press releases. Real-world threat actors including Kimsuky, Sandworm Team, and Silent Librarian have been observed collecting victim employee name information to support subsequent phishing campaigns, credential attacks, and social engineering operations. Detection is inherently challenging because this activity primarily occurs outside the victim's environment on public platforms. Effective detection pivots to monitoring organization-owned web properties for automated scraping, tracking OSINT tool execution on monitored endpoints, and identifying downstream artifacts such as systematic user enumeration via authentication systems.
MITRE ATT&CK
- Tactic
- Reconnaissance
- Technique
- T1589 Gather Victim Identity Information
- Sub-technique
- T1589.003 Employee Names
- Canonical reference
- https://attack.mitre.org/techniques/T1589/003/
LogScale Detection Query
// ── Branch 1: OSINT harvesting tool execution via Falcon EDR telemetry ────────
#event_simpleName = ProcessRollup2
| CommandLine = /(?i)(theHarvester|theharvester|recon\-ng|CrossLinked|crosslinked|linkedin2username|linkedin_username|phonebook\.cz|SpiderFoot|spiderfoot|maltego)/
OR FileName = /(?i)(theHarvester|crosslinked|linkedin2username|recon-ng)/
OR (
FileName = /(?i)python[23]?(\.exe)?$/
AND CommandLine = /(?i)(linkedin|harvest|employee|osint)/
)
| groupBy(
[ComputerName, UserName, FileName, CommandLine],
function=[
count(aid, as=EventCount),
min(@timestamp, as=FirstSeen),
max(@timestamp, as=LastSeen)
]
)
| eval ScrapeRisk = "HIGH - known OSINT tool on Falcon-managed endpoint"
| eval DetectionType = "Harvesting_Tool_Execution"
| sort(EventCount, order=desc)
| select([FirstSeen, LastSeen, DetectionType, ComputerName, UserName, FileName, CommandLine, EventCount, ScrapeRisk])
// ── Branch 2: DNS lookups to known OSINT/people-search platforms (deploy separately) ─
// #event_simpleName = DnsRequest
// | DomainName = /(?i)(hunter\.io|phonebook\.cz|rocketreach\.co|clearbit\.com|snov\.io|voilanorbert\.com|emailhunter\.co|findthat\.email|skrapp\.io|anymail\.io)/
// | groupBy(
// [ComputerName, UserName, DomainName],
// function=[
// count(ContextTimeStamp, as=QueryCount),
// min(@timestamp, as=FirstSeen),
// max(@timestamp, as=LastSeen)
// ]
// )
// | where QueryCount > 10
// | eval ScrapeRisk = "MEDIUM - repeated OSINT platform DNS queries from managed endpoint"
// | eval DetectionType = "OSINT_Platform_DNS_Enumeration"
// | sort(QueryCount, order=desc)CrowdStrike Falcon LogScale (CQL) detection for T1589.003 employee name harvesting. Branch 1 queries ProcessRollup2 events and applies regex matching against CommandLine and FileName fields for known OSINT harvesting tools — theHarvester, recon-ng, CrossLinked, linkedin2username, SpiderFoot, and maltego — including Python-invoked variants. Results are grouped by host, user, and command-line using groupBy with count/min/max aggregates. Branch 2 (commented, deploy separately) queries DnsRequest events for repeated lookups to known OSINT and people-search platform domains (hunter.io, Rocketreach, Clearbit, Snov.io, etc.) from managed endpoints, surfacing cases where adversaries use commercial enumeration services rather than open-source tools.
Data Sources
Required Tables
False Positives & Tuning
- Authorized penetration testers or red team operators using Falcon-managed workstations to execute theHarvester or recon-ng as part of a sanctioned engagement — validate against active engagement documentation and expected source hosts
- Security operations or threat intelligence analysts running SpiderFoot or Maltego for external attack surface assessment or vendor risk review on approved corporate endpoints — validate against security tooling allowlist
- Software developers testing or packaging OSINT tools in development environments where the Falcon sensor is deployed — the Python + 'linkedin'/'harvest' command-line branch may fire on legitimate CI/CD or testing workflows
Other platforms for T1589.003
Testing Methodology
Validate this detection against 5 adversary techniques from Atomic Red Team. Each test below lists the behaviour to exercise and the telemetry you should expect to see. Executable commands and cleanup steps are available with Pro.
- Test 1theHarvester Employee Name and Email Enumeration
Expected signal: Sysmon Event ID 1 (Linux auditd equivalent): process creation for 'theHarvester' or 'python3' with command line arguments '-d example.com -b google'. Sysmon Event ID 3 / auditd SYSCALL: outbound network connections to Google APIs and search endpoints. Sysmon Event ID 11: creation of /tmp/harvest_output.json. On Windows endpoints: DeviceProcessEvents with FileName=python.exe and ProcessCommandLine containing 'theHarvester' and '-b google'.
- Test 2CrossLinked LinkedIn Employee Name to Email Permutation
Expected signal: Sysmon Event ID 1: process create for python3 with CommandLine containing 'CrossLinked' or 'crosslinked' and '-f' and '{first}.{last}'. Sysmon Event ID 3: outbound DNS and TCP connections to linkedin.com and www.linkedin.com on port 443. Sysmon Event ID 11: file creation at /tmp/crosslinked_names.txt. DeviceProcessEvents (MDE): ProcessCommandLine containing 'crosslinked' or '{first}.{last}'.
- Test 3Corporate Team Page Automated Scraping Simulation
Expected signal: Sysmon Event ID 3 (Network Connect): repeated outbound connections to httpbin.org:443. Process creation for curl. In a real environment targeting a corporate web property: WAF/proxy logs showing 30+ requests to /team, /about-us, /staff URLs from the same source IP within 60 seconds with User-Agent 'Python-urllib/3.9'. CommonSecurityLog entries with RequestURL matching directory patterns.
- Test 4recon-ng LinkedIn Contacts Module Employee Enumeration
Expected signal: Sysmon Event ID 1: process create for recon-ng binary or python3 with recon-ng in command path. Sysmon Event ID 11: file creation in ~/.recon-ng/workspaces/employee_hunt/ including SQLite database data.db. Sysmon Event ID 3: outbound connections to linkedin.com, api.linkedin.com on port 443. DeviceProcessEvents: FileName containing 'recon-ng' or ProcessCommandLine containing 'recon-ng'.
- Test 5Hunter.io API Employee Name and Email Harvesting
Expected signal: Sysmon Event ID 3: outbound DNS query for api.hunter.io and TCP connection to api.hunter.io:443. Process creation for curl or python3 with api.hunter.io in command line arguments. In proxy/web access logs: GET requests to api.hunter.io/v2/domain-search with domain parameter. If monitoring DNS (Sysmon Event ID 22): DNS query for api.hunter.io.
References (10)
- https://attack.mitre.org/techniques/T1589/003/
- https://www.opm.gov/cybersecurity/cybersecurity-incidents/
- https://www.justice.gov/opa/pr/nine-iranians-charged-conducting-massive-cyber-theft-campaign-behalf-islamic-revolutionary
- https://www.cisa.gov/sites/default/files/publications/AA20-296A-Kimsuky_0.pdf
- https://github.com/laramies/theHarvester
- https://github.com/m8sec/CrossLinked
- https://github.com/lanmaster53/recon-ng
- https://docs.microsoft.com/en-us/azure/active-directory/reports-monitoring/reference-sign-ins-error-codes
- https://hunter.io/api-documentation/v2
- https://www.mandiant.com/resources/blog/apt29-domain-fronting-with-tor
Unlock Pro Content
Get the full detection package for T1589.003 including response playbook, investigation guide, and atomic red team tests.