ATT&CK coverage › Technique

Data Obfuscation: Protocol or Service Impersonation T1001.003

Adversaries may impersonate legitimate protocols or web service traffic to disguise command and control activity and thwart analysis efforts. By impersonating legitimate protocols or web services, adversaries can make their command and control traffic blend in with legitimate network traffic.

Events covered

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

ProviderEvent IDTitle
Sysmon11FileCreate
Security-Auditing5136A directory service object was modified.

Authoring guide

Patterns shared across the 2 rules above: which fields they filter on, what specific values they look for, and what they exclude. Field names are normalized 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
Image1match 1, ends_with 1\LANDesk\LDCLient\ldapwhoami.exe, :\windows\system32\svchost.exe, :\Program Files\Citrix\Receiver...
TargetFilename1ends_with 1, match 1\Local\Microsoft\Windows\SchCache\, .sch
AttributeLDAPDisplayName1eq 1primaryTelexNumber, primaryInternationalISDNNumber, otherFacsimileTelephoneNumber
AttributeValue1match 1*

Top indicator values (22 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.

FieldKindValueRules (here)Corpus reach
TargetFilenameends_with.sch1
Imageends_with:\Windows\CCM\CcmExec.exe1
Imageends_with:\windows\system32\dllhost.exe1
Imageends_with:\windows\system32\svchost.exe12
Imageends_with:\Windows\system32\dsac.exe1
Imagematch:\Program Files\SentinelOne\Sentinel Agent1
Imagematch:\Windows\ccmsetup\autoupgrade\ccmsetup1
Imagematch\Microsoft Office1
Imageends_with:\Windows\System32\wbem\WmiPrvSE.exe1
Imageends_with:\windows\system32\mmc.exe1
Imageends_with:\Program Files\Citrix\Receiver...1
Imageends_with\LANDesk\LDCLient\ldapwhoami.exe1
TargetFilenamematch\Local\Microsoft\Windows\SchCache\1
Imageends_with:\Windows\system32\efsui.exe1
Imagematch:\Program Files\16
Imageends_with\OUTLOOK.EXE13
Imageends_with:\windows\system32\WindowsPowerShell\v1.0\powershell.exe1
Imageends_with:\Program Files\Cylance\Desktop\CylanceSvc.exe1
AttributeValuematch*1
AttributeLDAPDisplayNameeqotherFacsimileTelephoneNumber1

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.

Sigma 2 rules