Compromise Accounts T1586

Tactic: Resource Development

Adversaries may compromise accounts with services that can be used during targeting. For operations incorporating social engineering, the utilization of an online persona may be important. Rather than creating and cultivating accounts (i.e. Establish Accounts), adversaries may compromise existing accounts. Utilizing an existing persona may engender a level of trust in a potential victim if they have a relationship, or knowledge of, the compromised persona.

Authoring guide

Patterns shared across the 41 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 (52 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
sourcetype30eq 30aws:cloudtrail, azure:monitor:aad, gws:reports:login, aws:asl, o365:management:activity
aws::eventName12eq 12ConsoleLogin, DeactivateMFADevice, DeleteVirtualMFADevice, GetPasswordData, ModifyDBInstance
category9eq 8, ends_with 1SignInLogs, AuditLogs, UserRiskEvents, signinlogs
signature6eq 6ConsoleLogin, user.authentication.auth_via_mfa, user.session.start
event.name5eq 5login_failure, login_success
properties.authenticationDetails{}.succeeded5eq 5false, true
properties.status.errorCode5eq 550126, 500121
aws::errorMessage3eq 3Failed authentication
isOutlier3eq 31
operationName3eq 2, contains 1Disable Strong Authentication, Sign-in activity, add member to role in pim completed
"additionalEventData.MFAUsed"2eq 2No, Yes
ErrorNumber2eq 250126
Operation2eq 2UserLoginFailed
Workload2eq 2AzureActiveDirectory
action2eq 2failure, success

Top indicator values (93 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
sourcetypeeq
aws:cloudtrail
959
sourcetypeeq
azure:monitor:aad
947
sourcetypeeq
gws:reports:login
55
sourcetypeeq
aws:asl
327
aws::eventNameeq
ConsoleLogin
627
aws::eventNameeq
DeactivateMFADevice
22
aws::eventNameeq
DeleteVirtualMFADevice
22
aws::eventNameeq
GetPasswordData
24
aws::eventNameeq
ModifyDBInstance
24
categoryeq
SignInLogs
612
event.nameeq
login_failure
44
signatureeq
ConsoleLogin
44
aws::errorMessageeq
Failed authentication
34
isOutliereq
1
328
properties.authenticationDetails{}.succeededeq
false
35
properties.status.errorCodeeq
50126
35
ErrorNumbereq
50126
22
Operationeq
UserLoginFailed
28
Workloadeq
AzureActiveDirectory
231
event.parameters{}.multiValue{}in
backup_code
22
event.parameters{}.multiValue{}in
google_authenticator
22
event.parameters{}.multiValue{}in
google_prompt
22
event.parameters{}.multiValue{}in
idv_any_phone
22
event.parameters{}.multiValue{}in
idv_preregistered_phone
22
event.parameters{}.multiValue{}in
internal_two_factor
22
event.parameters{}.multiValue{}in
knowledge_employee_id
22
event.parameters{}.multiValue{}in
knowledge_preregistered_email
22
event.parameters{}.multiValue{}in
knowledge_preregistered_phone
22
event.parameters{}.multiValue{}in
login_location
22
event.parameters{}.multiValue{}in
offline_otp
22

Exclusions (14 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
auth_msgeq
MFA successfully completed
1
event.parameters{}.multiValue{}in
backup_code
1
event.parameters{}.multiValue{}in
google_authenticator
1
event.parameters{}.multiValue{}in
google_prompt
1
event.parameters{}.multiValue{}in
idv_any_phone
1
event.parameters{}.multiValue{}in
idv_preregistered_phone
1
event.parameters{}.multiValue{}in
internal_two_factor
1
event.parameters{}.multiValue{}in
knowledge_employee_id
1
event.parameters{}.multiValue{}in
knowledge_preregistered_email
1
event.parameters{}.multiValue{}in
knowledge_preregistered_phone
1
event.parameters{}.multiValue{}in
login_location
1
event.parameters{}.multiValue{}in
offline_otp
1
event.parameters{}.multiValue{}in
security_key
1
event.parameters{}.multiValue{}in
security_key_otp
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

Splunk 36 rules

YARA-L 1 rule

Panther 1 rule