Inter-Process Communication: Component Object Model T1559.001

Tactic: Execution

Adversaries may use the Windows Component Object Model (COM) for local code execution. COM is an inter-process communication (IPC) component of the native Windows application programming interface (API) that enables interaction between software objects, or executable code that implements one or more interfaces. Through COM, a client object can call methods of server objects, which are typically binary Dynamic Link Libraries (DLL) or executables (EXE). Remote COM execution is facilitated by Remote Services such as Distributed Component Object Model (DCOM).

Events covered

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

Authoring guide

Patterns shared across the 17 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 (25 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
process_name10eq 10mshta.exe, cmd.exe, cscript.exe, excel.exe, mspub.exe
event.type9eq 9start
parent_process_name8eq 8dllhost.exe, explorer.exe, excel.exe, ieinstal.exe, iexplore.exe
Image5ends_with 3, is_not_null 1, wildcard 1\regsvr32.exe, \dllhost.exe, c:\*\appdata\*\temp\idc*.tmp\*.exe
Initiated5eq 5incoming, ingress, true
process.parent.args5eq 4, in 1-Embedding, /Processid:{3E5FC7F9-9A51-4367-9063-A120244FBEC7}, /Processid:{BD54C901-076B-434E-B6C7-17C531F4AB41}, /Processid:{D2E7041B-2927-42FB-8E9F-7CE93B6DC937}
DestinationPort3gt 2, ge 149151, 49152
EventType3eq 2, starts_with 1start, Image loaded
OriginalFileName3eq 1, in 1, ne 1cmd.exe, cscript.exe, mshta.exe, werfault.exe, xwizard.exe
Protocol3eq 3tcp
SourcePort3gt 2, ge 149151, 49152
dll.name3eq 3IEProxy.dll, msxml3.dll, taskschd.dll
src_ip3ne 3127.0.0.1, ::1
process.args2eq 2, wildcard 1-Embedding, RunWizard, {*}
CallTrace1contains 1cmlua.dll

Top indicator values (91 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
event.typeeq
start
9606
Initiatedeq
incoming
310
Initiatedeq
ingress
312
Initiatedeq
true
250
Protocoleq
tcp
318
process.parent.argseq
-Embedding
33
process_nameeq
mshta.exe
331
process_nameeq
regsvr32.exe
325
process_nameeq
rundll32.exe
360
process_nameeq
cmd.exe
277
process_nameeq
cscript.exe
225
process_nameeq
excel.exe
26
process_nameeq
mspub.exe
25
process_nameeq
powerpnt.exe
26
process_nameeq
powershell.exe
2104
process_nameeq
winword.exe
27
process_nameeq
wscript.exe
229
src_ipne
127.0.0.1
323
src_ipne
::1
321
DestinationPortgt
49151
22
EventTypeeq
start
216
Imageends_with
\regsvr32.exe
265
Imageends_with
\dllhost.exe
111
SourcePortgt
49151
22
parent_process_nameeq
dllhost.exe
27
parent_process_nameeq
explorer.exe
220
CallTracecontains
cmlua.dll
1
DestinationPortge
49152
13
DestinationPortNameeq
dns
15
EventTypestarts_with
Image loaded
110

Exclusions (37 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.

FieldKindValueRules excluding
Imageeq
?:\program files\wireguard\wireguard.exe
1
Imageeq
c:\windows\system32\clipup.exe
1
Imagewildcard
?:\program files (x86)\*exe
1
Imagewildcard
?:\program files\*.exe
1
Imagewildcard
?:\windows\splwow64.exe
1
Imagewildcard
?:\windows\system32\conhost.exe
1
Imagewildcard
?:\windows\system32\werfault.exe
1
Imagewildcard
?:\windows\syswow64\werfault.exe
1
dest_ipcidr_match
10.0.0.0/8
1
dest_ipcidr_match
127.0.0.0/8
1
dest_ipcidr_match
150.171.0.0/19
1
dest_ipcidr_match
169.254.0.0/16
1
dest_ipcidr_match
172.16.0.0/12
1
dest_ipcidr_match
192.168.0.0/16
1
dest_ipcidr_match
20.184.0.0/13
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 4 rules

Elastic 12 rules

Splunk 1 rule