ATT&CK coverage › Technique
Account Discovery T1087
Adversaries may attempt to get a listing of valid accounts, usernames, or email addresses on a system or within a compromised environment. This information can help adversaries determine which accounts exist, which can aid in follow-on behavior such as brute-forcing, spear-phishing attacks, or account takeovers (e.g., Valid Accounts).
Events covered
12 catalog events are tagged with this technique by at least one rule.
Authoring guide
Patterns shared across the 20 rules above: which fields they filter on, what specific values they look for, and what they exclude. Field names are normalized 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 (18 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 (824 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.
Common exclusions (8 distinct)
Field/operator/value combinations that rules under this technique routinely exclude (top-level not() clauses). 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.
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
- Chopper Webshell Process Pattern
- HackTool - SOAPHound Execution
- HackTool - winPEAS Execution
- Hacktool Ruler
- Malicious PowerShell Commandlets - PoshModule
- Malicious PowerShell Commandlets - ProcessCreation
- Malicious PowerShell Commandlets - ScriptBlock
- Network Reconnaissance Activity
- Potentially Suspicious EventLog Recon Activity Using Log Query Utilities
- PUA - Seatbelt Execution
- Suspicious Use of PsLogList
- Uncommon Connection to Active Directory Web Services
- Webshell Detection With Command Line Keywords
- Webshell Hacking Activity Patterns
Elastic 1 rule
Splunk 4 rules
- Enumerate Users Local Group Using Telegram
- Windows Account Discovery for Sam Account Name
- Windows Account Discovery With NetUser PreauthNotRequire
- Windows Special Privileged Logon On Multiple Hosts