Create or Modify System Process: Launch Agent T1543.001

Tactics: Persistence, Privilege Escalation

Adversaries may create or modify launch agents to repeatedly execute malicious payloads as part of persistence. When a user logs in, a per-user launchd process is started which loads the parameters for each launch-on-demand user agent from the property list (.plist) file found in /System/Library/LaunchAgents, /Library/LaunchAgents, and ~/Library/LaunchAgents. Property list files use the Label, ProgramArguments , and RunAtLoad keys to identify the Launch Agent's name, executable location, and execution time. Launch Agents are often installed to perform updates to programs, launch user specified programs at login, or to conduct other developer tasks.

Events covered

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

Authoring guide

Patterns shared across the 11 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 (14 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
host.os.type6eq 6
process_name5eq 2, starts_with 2, wildcard 1., bash, curl, java, launchctl
event.type4in 2, ne 2deletion, process_started, start
CommandLine3contains 3launchagents, runatload, launchdaemons, load, start
EventType3eq 3launch_daemon
Image3ends_with 2, starts_with 1/launchctl, /library/fonts/, /library/graphics/, /library/webserver/, /plistbuddy
TargetFilename2wildcard 2/library/launchagents/*, /library/launchagents/.*.plist, /library/launchdaemons/*, /library/launchdaemons/.*.plist, /system/library/launchagents/*
"columns.cmdline"1contains 1launchagents, runatload, true
Persistence.name1starts_with 1.
file.extension1eq 1plist
message1contains 1/library/launchagents, /library/launchdaemons, /system/library/launchagents
parent_process_name1eq 1launchd
process.args1eq 1load
subsystem1eq 1com.apple.launchd

Top indicator values (65 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
EventTypeeq
launch_daemon
33
CommandLinecontains
launchagents
22
CommandLinecontains
runatload
22
CommandLinecontains
true
23
CommandLinecontains
launchdaemons
1
CommandLinecontains
load
1
CommandLinecontains
start
113
CommandLinecontains
submit
1
event.typein
process_started
240
event.typein
start
242
event.typene
deletion
228
"columns.cmdline"contains
launchagents
1
"columns.cmdline"contains
runatload
1
"columns.cmdline"contains
true
1
Imageends_with
/launchctl
12
Imageends_with
/plistbuddy
12
Imagestarts_with
/library/fonts/
1
Imagestarts_with
/library/graphics/
1
Imagestarts_with
/library/webserver/
1
Imagestarts_with
/private/tmp/
14
Imagestarts_with
/private/var/root/library/
1
Imagestarts_with
/tmp/
125
Imagestarts_with
/users/shared/
14
Imagestarts_with
/var/folders/
12
Imagestarts_with
/var/root/
12
Imagestarts_with
/var/tmp/
124
Persistence.namestarts_with
.
1
TargetFilenamewildcard
/library/launchagents/*
1
TargetFilenamewildcard
/library/launchagents/.*.plist
1
TargetFilenamewildcard
/library/launchdaemons/*
1

Exclusions (17 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
/opt/chef/embedded/bin/ruby
1
Imagein
/bin/bash
1
Imagein
/usr/bin/sed
1
Imagestarts_with
/library/privilegedhelpertools/
1
Imagestarts_with
/system/
1
file.namewildcard
.!*!*.plist
1
file.namewildcard
.chef-com*.plist
1
messagecontains
com.apple.
1
process.code_signature.signing_idin
com.apple.cat
1
process.code_signature.signing_idin
com.apple.cfprefsd
1
process.code_signature.signing_idin
com.apple.ditto
1
process.code_signature.signing_idin
com.apple.pico
1
process.code_signature.signing_idin
com.apple.shove
1
process.code_signature.signing_idin
com.apple.vim
1
process.code_signature.signing_idin
com.jetbrains.toolbox
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 3 rules

Elastic 6 rules

Splunk 2 rules