ATT&CK coverage › Technique

Obfuscated Files or Information: Command Obfuscation T1027.010

Adversaries may obfuscate content during command execution to impede detection. Command-line obfuscation is a method of making strings and patterns within commands and scripts more difficult to signature and analyze. This type of obfuscation can be included within commands executed by delivered payloads (e.g., Phishing and Drive-by Compromise) or interactively via Command and Scripting Interpreter.

Events covered

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

ProviderEvent IDTitle
Sysmon1Process creation
Sysmon13RegistryEvent (Value Set)
Security-Auditing4688A new process has been created.
PowerShell4104Creating Scriptblock text (MessageNumber of MessageTotal).

Authoring guide

Patterns shared across the 19 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 (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
Esql.script_block_pattern_count10ge 101, 2, 20, 5
Esql.script_block_length8gt 8500, 1000
CommandLine5match 5InstallProduct(, .Insert(, UILevel, #-, #+
file.directory4is_null 4
ScriptBlockText3match 3+, `, {0}
Image3ends_with 2, match 1\powershell.exe, \pwsh.exe, \powershell_ise.exe, \rundll32.exe, \python
OriginalFileName3eq 2, match 1PowerShell.EXE, pwsh.dll, PowerShell_ISE.EXE, RUNDLL32.EXE, python
Esql.script_block_ratio2gt 1, ge 10.5, 0.75
file.name2is_null 2
Details2match 2            ,             ,             
TargetObject2match 1, ends_with 1\Software\Microsoft\Windows\CurrentVersion\Explorer\RunMRU\, \Software\Microsoft\Windows\CurrentVersion\Explorer\Typed...
powershell.file.script_block_unique_symbols1lt 150
ParentImage1ends_with 1\explorer.exe
ParentCommandLine1match 1tokens=, dir, in (

Top indicator values (81 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
Esql.script_block_pattern_countge166
Esql.script_block_lengthgt50066
Esql.script_block_lengthgt100022
Esql.script_block_pattern_countge222
Detailsmatch            22
Detailsmatch            22
Detailsmatch            22
Detailsmatch#23
Detailsmatch            22
Detailsmatch 22
Detailsmatch            22
Detailsmatch            22
Detailsmatch            22
Detailsmatch            22
Detailsmatch            22
Detailsmatch            22
Detailsmatch            22
Detailsmatch            22
ScriptBlockTextmatch+1
Esql.script_block_ratiogt0.51

Common exclusions (9 distinct)

Field/operator/value combinations that rules under this technique routinely exclude (top-level not() clauses). 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.

FieldKindValueRules excluding
ScriptBlockTextmatch[System.IO.File]::Open('C:\\\\ProgramData\\\\Microsoft\\\\Windows Defender...1
ScriptBlockTextmatch$([char]0x1b)]6331
ScriptBlockTextmatch:::::\\\\windows\\\\sentinel1
ScriptBlockTextmatch$local:Bypassed1
ScriptBlockTextmatchorigPSExecutionPolicyPreference1
ScriptBlockTextmatch$s.BranchBehindStatusSymbol.Text1
ScriptBlockTextmatchGitBranchStatus1
ScriptBlockTextmatchsentinelbreakpoints1
ScriptBlockTextmatchGENESIS-56541

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 7 rules

Elastic 12 rules