AN0999: Analytic 0999
macOS permission and attribute manipulation behavioral chain: (1) Process execution of permission utilities (chmod, chown, chgrp) or macOS-specific tools (chflags) with suspicious parameters, (2) System Integrity Protection (SIP) bypass attempts through permission modifications, (3) File flags manipulation (uchg, schg, hidden) for evasion or persistence, (4) Extended attribute (xattr) modifications affecting security metadata, (5) Unified log correlation with file system events and subsequent access patterns, (6) Gatekeeper and code signing bypass through permission/attribute manipulation
Analyst context for executives and security teams
AN0999 is a macOS-focused detection analytic for suspicious permission, ownership, file flag, and extended attribute changes. Its practical value is that these changes can affect whether software is trusted, hidden, protected from modification, or able to persist. For leaders, this is a coverage question: can the organization see and investigate macOS file-system metadata changes that may weaken platform security controls such as Gatekeeper, code signing expectations, or System Integrity Protection-related protections?
Executive priority
Prioritize this where macOS endpoints support privileged users, developers, administrators, executives, or regulated workflows. The business issue is not a single command; it is whether endpoint monitoring and incident response can prove when important macOS security metadata was changed, by which process or user, and what happened afterward. This matters for operational resilience, audit evidence, and response decisions when suspicious software or persistence is investigated on macOS systems.
Technical view
Validate whether SOC and IR teams can correlate macOS process execution of permission and metadata utilities such as chmod, chown, chgrp, chflags, and xattr with file-system events, Unified Log data, and subsequent access patterns. The analytic description highlights suspicious parameters, SIP bypass attempts through permission modifications, file flag changes such as uchg, schg, or hidden, extended attribute changes affecting security metadata, and possible Gatekeeper or code-signing bypass through permission or attribute manipulation. ATT&CK does not provide official detection logic for this analytic, so local engineering must define baselines, exclusions, and severity based on protected paths, sensitive applications, user context, and change intent.
Likely telemetry
- macOS process execution telemetry, including command line arguments for chmod, chown, chgrp, chflags, and xattr
- File-system event telemetry showing permission, ownership, flag, and extended attribute changes
- macOS Unified Log records correlated with file-system and process activity
- Endpoint telemetry showing user, parent process, target file path, and subsequent access patterns
- Security control evidence related to Gatekeeper, code signing, and System Integrity Protection-relevant events where available
Detection direction
- Confirm collection includes command-line arguments and target paths for macOS permission and attribute utilities; process names alone will be too noisy and low value.
- Tune for suspicious combinations: security-sensitive paths, unexpected parent processes, unusual users, changes to flags such as uchg, schg, or hidden, and extended attribute changes affecting security metadata.
- Correlate permission or attribute changes with later execution, access, persistence-like behavior, or security control bypass indicators rather than alerting on every administrative change.
- Build allowlists carefully for software management, developer tooling, backup agents, and legitimate administrative scripts to reduce false positives.
- Because no official detection logic is supplied, test coverage with benign administrative scenarios and known enterprise management workflows before relying on alert quality.
Mitigation priorities
- Establish a macOS asset and role baseline so high-risk endpoints and sensitive paths receive stronger monitoring first.
- Restrict and monitor administrative privilege use on macOS systems, especially for users and tools capable of changing ownership, permissions, file flags, and extended attributes.
- Ensure endpoint logging retains process command lines, file metadata changes, and Unified Log context long enough to support incident response and compliance evidence.
- Review macOS hardening and management practices around Gatekeeper, code signing expectations, and System Integrity Protection-relevant configuration, without assuming telemetry alone prevents misuse.
- Document approved administrative and software-management behaviors so SOC teams can distinguish expected maintenance from suspicious metadata manipulation.
Analyst notes and limits
This object is a detection analytic, not a technique or procedure, and no tactics or relationships were supplied. The strongest use is as a coverage validation item for macOS endpoint monitoring and IR readiness around file permission and metadata manipulation.
The official ATT&CK fields provide a behavioral description but no official detection query, tactic mapping, related techniques, adversary relationships, or mitigation text. Any production detection, severity model, or business exposure assessment requires local macOS telemetry, asset criticality, administrative workflows, and endpoint control configuration.
Analytic 0999
macOS permission and attribute manipulation behavioral chain: (1) Process execution of permission utilities (chmod, chown, chgrp) or macOS-specific tools (chflags) with suspicious parameters, (2) System Integrity Protection (SIP) bypass attempts through permission modifications, (3) File flags manipulation (uchg, schg, hidden) for evasion or persistence, (4) Extended attribute (xattr) modifications affecting security metadata, (5) Unified log correlation with file system events and subsequent access patterns, (6) Gatekeeper and code signing bypass through permission/attribute manipulation
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
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Imported snapshots across ATT&CK releases (1)
| Release | Bundle imported | Object version | Modified | Status | Raw hash |
|---|---|---|---|---|---|
| 19.1 | 1.0 | Current bundle | 4dce5b6af6d6… |
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
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mitre-attack AN0999Open source URL
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