Office Application Startup: Office Test T1137.002

Tactic: Persistence

Adversaries may abuse the Microsoft Office "Office Test" Registry key to obtain persistence on a compromised system. An Office Test Registry location exists that allows a user to specify an arbitrary DLL that will be executed every time an Office application is started. This Registry key is thought to be used by Microsoft to load DLLs for testing and debugging purposes while developing Office applications. This Registry key is not created by default during an Office installation.

Events covered

4 catalog events are tagged with this technique by at least one rule.

Authoring guide

Patterns shared across the 3 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 (4 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.

FieldRulesHowSample values
TargetObject2contains 2\software\microsoft\office test\special\perf, \software\microsoft\office test\special\perf\
EventType1ne 1deletion
Image1ends_with 1/bash, /curl, /dash
ParentImage1contains 1microsoft excel, microsoft onenote, microsoft powerpoint

Top indicator values (18 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.

FieldKindValueRules (here)Corpus reach
EventTypene
deletion
111
Imageends_with
/bash
113
Imageends_with
/curl
122
Imageends_with
/dash
19
Imageends_with
/fish
14
Imageends_with
/osacompile
12
Imageends_with
/osascript
17
Imageends_with
/python
18
Imageends_with
/python3
15
Imageends_with
/sh
112
Imageends_with
/wget
114
Imageends_with
/zsh
17
ParentImagecontains
microsoft excel
1
ParentImagecontains
microsoft onenote
1
ParentImagecontains
microsoft powerpoint
1
ParentImagecontains
microsoft word
1
TargetObjectcontains
\software\microsoft\office test\special\perf
1
TargetObjectcontains
\software\microsoft\office test\special\perf\
1

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.

Platform (all)
Domain (all)

Sigma 2 rules

Elastic 1 rule