AN0255: Analytic 0255
Adversary runs commands like `whoami`, `id`, `w`, or `cat /etc/passwd` from non-interactive or scripting contexts to enumerate system user details.
Analyst context for executives and security teams
This analytic matters because basic Linux user-enumeration commands can be an early sign that a script or non-interactive process is checking account context and local users. For leaders, the decision value is not the commands themselves—they are common administrative utilities—but whether the organization can distinguish expected automation from suspicious command execution in Linux environments.
Executive priority
Prioritize this as a Linux visibility and triage-readiness question. Security leaders should ask whether SOC and IR teams can show evidence of command execution context, parent process, user identity, and script-driven activity for Linux systems. Because the ATT&CK object provides no tactic, relationship, or official detection logic, it should not drive standalone risk conclusions; it should support broader control validation around endpoint logging, managed detection quality, and incident investigation readiness.
Technical view
Validate whether Linux telemetry can identify execution of commands such as `whoami`, `id`, `w`, and reads of `/etc/passwd` when launched from non-interactive or scripting contexts. Detection engineering should focus on context: parent process, shell or interpreter use, process lineage, effective user, host role, command frequency, and whether execution aligns with known automation. Since no official detection is supplied, teams should treat this as an analytic design prompt rather than a ready-to-deploy rule.
Likely telemetry
- Linux process creation events with command line arguments
- Parent-child process lineage for shells, scripts, and interpreters
- User identity and effective user context for executed commands
- File access or command-line evidence involving `/etc/passwd`
- Host role and automation context, such as scheduled jobs or management scripts, where available
Detection direction
- Baseline legitimate administrative and automation use of `whoami`, `id`, `w`, and `/etc/passwd` reads before alerting broadly.
- Tune around non-interactive execution context, including script interpreters, shells without user login sessions, and automated job contexts.
- Correlate command execution with parent process, account, host role, and recent activity rather than treating the command names alone as suspicious.
- Expect false positives from configuration management, monitoring agents, login scripts, compliance checks, and administrative troubleshooting.
- Because no ATT&CK relationships or official detection logic are supplied, validate locally against real Linux telemetry before using this analytic for SOC alerting or compliance evidence.
Mitigation priorities
- Ensure Linux endpoints that matter to business operations produce process execution telemetry with command line and user context.
- Document and inventory expected automation that runs identity or user-enumeration commands.
- Apply least-privilege and account governance so script-driven enumeration does not expose unnecessary access context.
- Use this analytic to test SOC runbooks: analysts should be able to determine whether the activity came from an approved script, administrator action, or unexplained process chain.
- Retain sufficient Linux endpoint logs to support incident response reconstruction when user-enumeration behavior appears in a larger investigation.
Analyst notes and limits
The supplied object is a detection analytic for Linux only. It describes commands used to enumerate system user details from non-interactive or scripting contexts. There are no supplied tactics, relationships, aliases, labels, or official detection text, so interpretation should remain conservative and environment-specific.
This take is limited to the supplied ATT&CK fields and the single external reference. It does not establish adversary attribution, active exploitation, impact, or guaranteed detection coverage. Local baselines, host roles, and telemetry quality are required to decide whether observed command execution is suspicious.
Analytic 0255
Adversary runs commands like `whoami`, `id`, `w`, or `cat /etc/passwd` from non-interactive or scripting contexts to enumerate system user details.
How security teams should use this page
Treat this object as behavior context, not an attribution claim. Validate the related groups, software, data sources, and mitigations against official ATT&CK relationships and your own telemetry before making control-coverage decisions.
All related ATT&CK context
No relationships are available in the current normalized data for this object.
Object version and sync metadata
The fields below describe the current mirrored snapshot. When Glexia retains multiple ATT&CK source imports, you can open the table to compare the same object across releases (hashes and MITRE timestamps). For MITRE’s own release notes and roadmap, see ATT&CK resources — Updates .
Imported snapshots across ATT&CK releases (1)
| Release | Bundle imported | Object version | Modified | Status | Raw hash |
|---|---|---|---|---|---|
| 19.1 | 1.0 | Current bundle | 8b4b6e89742f… |
Mirrored ATT&CK source object
The raw object is retained through the mirrored ATT&CK source bundle and object hash. The raw endpoint returns the exact object from the mirrored bundle when available.
External references and citations
MITRE external references are preserved separately from Glexia analysis so citations remain traceable to their original source records.
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[1]
mitre-attack AN0255Open source URL
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