Office Application Startup T1137
Adversaries may leverage Microsoft Office-based applications for persistence between startups. Microsoft Office is a fairly common application suite on Windows-based operating systems within an enterprise network. There are multiple mechanisms that can be used with Office for persistence when an Office-based application is started; this can include the use of Office Template Macros and add-ins.
Events covered
7 catalog events are tagged with this technique by at least one rule.
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
| Sysmon | Event ID 11 | FileCreate |
| Sysmon | Event ID 12 | RegistryEvent (Object create and delete) |
| Sysmon | Event ID 13 | RegistryEvent (Value Set) |
| Sysmon | Event ID 14 | RegistryEvent (Key and Value Rename) |
| Security-Auditing | Event ID 4688 | A new process has been created. |
| PowerShell | Event ID 4104 | Creating Scriptblock text (MessageNumber of MessageTotal). |
Authoring guide
Patterns shared across the 21 rules above: which fields they filter on, what specific values they look for, and what they exclude. The catalog normalizes field names 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 (12 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 (127 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. Click a value to expand the rules under this technique that use it.
Exclusions (48 distinct)
Field/operator/value combinations excluded by rules under this technique (top-level not() clauses), sorted by how many rules exclude each. 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. Click a value to expand the rules under this technique that exclude it.
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 15 rules
- Code Executed Via Office Add-in XLL File
- IE Change Domain Zone
- New Outlook Macro Created
- Office Application Startup - Office Test
- Outlook Macro Execution Without Warning Setting Enabled
- Outlook Security Settings Updated - Registry
- Outlook Task/Note Reminder Received
- Potential Persistence Via Excel Add-in - Registry
- Potential Persistence Via Microsoft Office Add-In
- Potential Persistence Via Microsoft Office Startup Folder
- Potential Persistence Via Outlook Form
- Potential Persistence Via Outlook LoadMacroProviderOnBoot Setting
- Potential Persistence Via Visual Studio Tools for Office
- Registry Modification to Hidden File Extension
- Suspicious Outlook Macro Created
Elastic 3 rules
- Office Test Registry Persistence
- Outlook Home Page Registry Modification
- Suspicious Execution via Microsoft Office Add-Ins