Malicious Shell or osascript Spawned by Microsoft Office on macOS

ATT&CK techniques

Initial Access → Execution

Recon
Resource Dev
Initial Access
- T1566.001Spearphishing Attachment
Execution
- T1059.002AppleScript
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects a Microsoft Office application on macOS spawning a shell or osascript which is the macro driven initial access chain described in the WithSecure macOS lab where a Word AutoOpen macro ran a shell script through osascript. An Office app launching a scripting interpreter almost always indicates malicious macro execution following a phishing document.

Reporting behind it

Related detections9 linkedT1059.002 — drag to rearrange

Suspicious osascript Executing JavaScript Payload from Office Container

Malicious Office Application Spawning Script Interpreter

Malicious Credential Phishing Dialog via osascript

Suspicious Office Application Spawning Regsvr32 via Process Chain (via process_creation)

Suspicious OneNote Spawning Command or Script Interpreter via Spear-Phishing (via process_creation)

Malicious Data Exfiltration via curl with Stealer Specific BuildID Header

Suspicious osascript Password Prompt via AppleScript Display Dialog (via process_creation)

Malicious Sapphire Sleet curl to osascript Chain With mac-cur User-Agent (via process_creation)

Suspicious RDP Connection File Opened From Download or Mail Directory via Process Creation

Malicious Shell or osascript Spawned by Microsoft Office on macOS

Pivot detection · T1059.002 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

Full detection rule

Unlock this rule to view and copy it

The detection logic is included with a plan. Everything else — context, mappings and implementation details — stays free on this page.

Sign in for 3 free unlocks

Signing in gives you 3 unlocks to spend on any rule in the library. No card, and they do not expire.

Also included

Unlocked rules convert on this page — to Splunk SPL or Splunk — Raw Index SPL or Microsoft Sentinel KQL or Microsoft Sentinel ASIM ASIM KQL or Microsoft Defender XDR KQL or Elastic Security KQL or Elastic Security Lucene or Elastic Security ES|QL or CrowdStrike Falcon CQL or SentinelOne PowerQuery or Palo Alto Cortex XDR XQL or Carbon Black Cloud Platform Search or Carbon Black EDR Process Search or Google Security Operations UDM Search or IBM QRadar AQL or Sumo Logic Cloud SIEM Rules expression or Rapid7 InsightIDR LEQL or Graylog Search or OpenSearch Lucene or OpenSearch PPL PPL or Grafana Loki LogQL or SQLite SQL or Zircolite SQLite — with the log-source profile the engine picked, the field map it used, and everything it could not express. Converting a rule you have unlocked costs no further credit.

See it run on a free rule →Convert your own rule →