Shared Modules T1129

Tactic: Execution

Adversaries may execute malicious payloads via loading shared modules. Shared modules are executable files that are loaded into processes to provide access to reusable code, such as specific custom functions or invoking OS API functions (i.e., Native API).

Events covered

5 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 (27 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
ImageLoaded7starts_with 3, ends_with 2, contains 1, ne 1, wildcard 1*.dll, .node, .vscode\extensions\ms-toolsai.jupyter-, /users/, ?:\users\*\appdata\local\temp\wps\inetcache\*
process_name5eq 4, starts_with 1cmd.exe, excel.exe, msaccess.exe, powerpnt.exe, powershell.exe
EventType4eq 1, in 1, starts_with 1, wildcard 1load, Image loaded, Image loaded*, ProcessRollup2, exec
TargetFilename4wildcard 2, ends_with 1, eq 1*\\windowspowershell\\modules\\*.dll, .xll, ?:\users\*\appdata\local\temp\wps\inetcache\*, \\*, \device\harddiskvolume*\*\*.exe.local\*.dll
event.type4eq 4start, change
EventID3eq 37, 4104
Image3ends_with 1, eq 1, wildcard 1?:\windows\system32\dns.exe, \code.exe, c:\program files (x86)\webhelpdesk\*\java*.exe, c:\program files\webhelpdesk\*\java*.exe
event.category3eq 3library, process
SignatureStatus2eq 1, ne 1Unavailable, Valid
Signed2eq 1, ne 1false, true
dll.code_signature.trusted2eq 1, ne 1false, true
host.os.type2eq 2
parent_process_name2eq 1, in 1OpenWith.exe, cmd.exe, cupsd, explorer.exe, foomatic-rip
process.args2wildcard 2, contains 1, eq 1.+\.(wll|xll|ppa|ppam|xla|xlam|vsto), /RunHandlerComServer, /UpdateDeploymentProvider, ?:\ProgramData\*, ?:\Users\*\AppData\Roaming\*
CommandLine1wildcard 1*/dev/shm/*, */dev/tcp*, */dev/tcp/*

Top indicator values (137 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
4606
event.categoryeq
library
313
event.categoryeq
process
3128
EventIDeq
7
239
CommandLinewildcard
*/dev/shm/*
13
CommandLinewildcard
*/dev/tcp*
12
CommandLinewildcard
*/dev/tcp/*
12
CommandLinewildcard
*/dev/udp/*
12
CommandLinewildcard
*/etc/init.d*
12
CommandLinewildcard
*/etc/ld.so*
12
CommandLinewildcard
*/etc/passwd*
14
CommandLinewildcard
*/etc/profile*
12
CommandLinewildcard
*/etc/rc.local*
12
CommandLinewildcard
*/etc/shadow*
15
CommandLinewildcard
*/etc/ssh*
14
CommandLinewildcard
*/etc/sudoers*
12
CommandLinewildcard
*/etc/update-motd.d*
12
CommandLinewildcard
*/home/*/.ssh/*
15
CommandLinewildcard
*/root/.ssh*
13
CommandLinewildcard
*/var/tmp*
1
CommandLinewildcard
*>>*
1
CommandLinewildcard
*Fiddle.dlopen*.so*
1
CommandLinewildcard
*GS_ARGS=*
1
CommandLinewildcard
*TCPSocket.new*
12
CommandLinewildcard
*TCPSocket.open*
12
CommandLinewildcard
*autostart*
12
CommandLinewildcard
*base32 *
1
CommandLinewildcard
*base64 *
12
CommandLinewildcard
*cdll.LoadLibrary*.so*
1
CommandLinewildcard
*cron*
12

Exclusions (27 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
Imageends_with
\code.exe
1
ImageLoadedcontains
.vscode\extensions\ms-toolsai.jupyter-
1
ImageLoadedends_with
\electron.napi.node
1
ImageLoadedends_with
\node.napi.glibc.node
1
ImageLoadedwildcard
*/site-packages/*/qt*/lib/qt*.framework/versions/*/qt*
1
ImageLoadedwildcard
/users/*/.pyenv/versions/*/lib/python*/site-packages/*
1
ParentImagewildcard
?:\program files\common files\microsoft shared\vsto\*\vstoinstaller.exe
1
ParentImagewildcard
?:\program files\logioptionsplus\plugininstallerutility*.exe
1
ParentImagewildcard
?:\program files\logitech\logioptions\plugininstallerutility*.exe
1
ParentImagewildcard
?:\program files\logitech\logioptions\plugininstallerutility.exe
1
ParentImagewildcard
?:\programdata\logishrd\logioptions\plugins\vsto\*\vstoinstaller.exe
1
ParentImagewildcard
?:\programdata\logishrd\logioptionsplus\plugins\vsto\*\vstoinstaller.exe
1
SubjectUserNameeq
%sap_admin_users.user
1
TargetFilenamein
*:\\program files\\microsoft office\\*
1
TargetFilenamein
*\\appdata\\roaming\\microsoft\\addins\\*
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 8 rules

Splunk 5 rules

YARA-L 2 rules