AN1039: Analytic 1039
Detect unauthorized `trap` command registrations in shell startup files (e.g., .zprofile, .bash_profile, .zshrc) followed by execution chains during user terminal interaction. Use Unified Logs and EDR telemetry to correlate shell command parsing and process tree anomalies.
Analyst context for executives and security teams
This analytic matters because it focuses on persistence-like behavior in macOS user shell startup files: unauthorized `trap` command registrations that can run command chains when a user interacts with a terminal. For leaders, the practical risk is not the specific shell syntax alone, but whether endpoint monitoring can see tampering in user startup files and correlate it with suspicious process execution during normal administrative or developer activity.
Executive priority
Prioritize this as a macOS endpoint visibility and response-readiness validation item. Organizations with macOS engineering, administrator, or power-user populations should confirm that managed detection, incident response, and audit evidence cover shell startup file changes, Unified Logs, EDR process trees, and user-context execution. The business question is: if a user profile is modified to trigger commands during terminal use, would the SOC know quickly enough to investigate before the behavior blends into normal developer or admin workflows?
Technical view
The supplied analytic is scoped to macOS and describes detection of unauthorized `trap` command registrations in shell startup files such as `.zprofile`, `.bash_profile`, and `.zshrc`, followed by execution chains during user terminal interaction. SOC and detection engineering teams should validate collection and correlation between file modification events, shell command parsing indicators where available, Unified Logs, and EDR process tree anomalies. Because no ATT&CK tactic, technique relationship, or formal detection logic is supplied, implementation should be treated as a local detection engineering exercise rather than a complete ready-to-run rule.
Likely telemetry
- macOS Unified Logs relevant to shell activity and user terminal interaction
- EDR process creation and parent-child process tree telemetry
- File modification telemetry for user shell startup files including `.zprofile`, `.bash_profile`, and `.zshrc`
- Command-line or shell execution metadata where available
- User identity, host, and timestamp context to correlate startup file changes with later terminal-driven execution
Detection direction
- Baseline legitimate shell startup file content for macOS users with frequent terminal use, especially administrators and developers.
- Alert or review newly added or changed `trap` registrations in shell startup files, with emphasis on changes followed by unusual execution chains.
- Correlate file modification time, modifying process or user, subsequent shell launches, and child process behavior rather than relying on a single string match.
- Tune for expected administrative customization to reduce false positives; shell profile customization can be normal in developer environments.
- Validate blind spots around unmanaged Macs, incomplete EDR command-line capture, limited Unified Log retention, and lack of file integrity visibility in user home directories.
Mitigation priorities
- Ensure macOS endpoints in scope are enrolled in endpoint monitoring capable of collecting process trees, command metadata, and relevant file modification events.
- Apply least-privilege and administrative hygiene so unauthorized changes to user environments are easier to investigate and contain.
- Establish response procedures for suspicious shell startup file modifications, including preserving file contents, timestamps, user context, and related process telemetry.
- Use configuration management or endpoint hardening practices to identify unexpected changes to shell startup files on high-value systems.
- Review logging retention and SOC runbooks so responders can connect profile-file modification to later terminal activity.
Analyst notes and limits
This Glexia take is based only on the supplied MITRE analytic fields. The object is a detection analytic, AN1039, for macOS, describing unauthorized `trap` registrations in shell startup files and correlation with Unified Logs and EDR telemetry. No relationships, aliases, labels, tactics, or official detection logic were supplied.
Coverage cannot be inferred from the ATT&CK object alone. The source does not provide a formal rule, query, tactic mapping, related technique, adversary usage, or exploitation context. Local validation is required to determine whether telemetry exists, whether `trap` usage is legitimate in the environment, and whether detections produce acceptable fidelity.
Analytic 1039
Detect unauthorized `trap` command registrations in shell startup files (e.g., .zprofile, .bash_profile, .zshrc) followed by execution chains during user terminal interaction. Use Unified Logs and EDR telemetry to correlate shell command parsing and process tree anomalies.
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 | 8bbe58dcef99… |
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.
-
[1]
mitre-attack AN1039Open source URL
Source: MITRE ATT&CK®. © 2026 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation. MITRE ATT&CK and ATT&CK are registered trademarks of The MITRE Corporation. Glexia is not affiliated with or endorsed by MITRE.