Invoke-Obfuscation CLIP+ Launcher

Status: test
Severity: high
Log source: product windows, category process_creation
Author: Jonathan Cheong, oscd.community
Source: github.com/SigmaHQ/sigma

Detects Obfuscated use of Clip.exe to execute PowerShell

MITRE ATT&CK coverage

Tactic	Techniques
Execution	`T1059.001` Command and Scripting Interpreter: PowerShell
Stealth	`T1027` Obfuscated Files or Information

Event coverage

Provider	Event	Title
Sysmon	Event ID 1	Process creation
Security-Auditing	Event ID 4688	A new process has been created.

Rule body yaml

title: Invoke-Obfuscation CLIP+ Launcher
id: b222df08-0e07-11eb-adc1-0242ac120002
status: test
description: Detects Obfuscated use of Clip.exe to execute PowerShell
references:
    - https://github.com/SigmaHQ/sigma/issues/1009  # (Task 26)
author: Jonathan Cheong, oscd.community
date: 2020-10-13
modified: 2022-11-17
tags:
    - attack.stealth
    - attack.t1027
    - attack.execution
    - attack.t1059.001
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        # CommandLine|re: 'cmd.{0,5}(?:\/c|\/r).+clip(?:\.exe)?.{0,4}&&.+clipboard]::\(\s\\\"\{\d\}.+\-f.+\"'
        # Example 1: Cmd /c" echo/Invoke-Expression (New-Object Net.WebClient).DownloadString |cLiP&& POWerSheLl -Nolog -sT . (\"{1}{2}{0}\"-f'pe','Ad',(\"{1}{0}\" -f'Ty','d-' ) ) -Assemb ( \"{5}{1}{3}{0}{2}{4}\" -f'ows','y','.F',(\"{0}{1}{2}\" -f'stem.W','i','nd'),( \"{0}{1}\"-f 'o','rms' ),'S' ) ; ([SySTEM.wiNDows.FoRmS.CLiPbOArd]::( \"{1}{0}\" -f (\"{1}{0}\" -f'T','TTeX' ),'gE' ).\"invO`Ke\"( ) ) ^| ^&( \"{5}{1}{2}{4}{3}{0}\" -f 'n',( \"{1}{0}\"-f'KE-','o' ),(\"{2}{1}{0}\"-f 'pRESS','x','e' ),'o','i','iNV') ; [System.Windows.Forms.Clipboard]::(\"{0}{1}\" -f( \"{1}{0}\"-f'e','SetT' ),'xt').\"InV`oKe\"( ' ')"
        # Example 2: CMD/c " ECho Invoke-Expression (New-Object Net.WebClient).DownloadString|c:\WiNDowS\SySteM32\cLip && powershElL -noPRO -sTa ^& (\"{2}{0}{1}\" -f 'dd',(\"{1}{0}\"-f 'ype','-T' ),'A' ) -AssemblyN (\"{0}{3}{2}{1}{4}\"-f'Pr','nCo',(\"{0}{1}\"-f'e','ntatio'),'es','re' ) ; ^& ( ( [StRinG]${ve`RB`OSE`pr`e`FeReNCE} )[1,3] + 'x'-JoiN'') ( ( [sySTem.WInDOWs.ClipbOaRD]::( \"{1}{0}\" -f(\"{0}{1}\" -f'tTe','xt' ),'ge' ).\"IN`Vo`Ke\"( ) ) ) ; [System.Windows.Clipboard]::( \"{2}{1}{0}\" -f't',( \"{0}{1}\" -f 'tT','ex' ),'Se' ).\"In`V`oKe\"( ' ' )"
        CommandLine|contains|all:
            - 'cmd'
            - '&&'
            - 'clipboard]::'
            - '-f'
        CommandLine|contains:
            - '/c'
            - '/r'
    condition: selection
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: `condition`

selection

Stage 1: `selection`

selection:
    CommandLine|contains|all:
        - 'cmd'
        - '&&'
        - 'clipboard]::'
        - '-f'
    CommandLine|contains:
        - '/c'
        - '/r'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

Field	Kind	Values
`CommandLine`	match	`&&` corpus 2 (sigma 2) `-f` corpus 9 (sigma 7, splunk 2) `/c` corpus 15 (sigma 13, splunk 2) `/r` corpus 3 (sigma 3) `clipboard]::` `cmd` corpus 8 (sigma 8)

`j` / `k`	Scroll down / up
`d` / `u`	Half-page down / up
`gg` / `G`	Top / bottom
`h` / `l`	History back / forward
`f`	Follow link (`Shift` = new tab)
`/`	Focus search
`?`	Toggle this help
`↑` / `↓`	Navigate search results
`Enter`	Open highlighted result
`Esc`	Close results / dialog

`type:`	`events` / `rules` / `providers`
`vendor:`	`sigma` / `elastic` / `splunk` / `kusto` / `chronicle` (vendor name alone also works: `sigma:`, `kql:`, `secops:`…)
`tactic:`	TA-id, slug, or name: `credential_access`, `TA0006`
`technique:`	technique or sub-technique ID: `T1003`, `T1003.001` (alias `tech:`)
`severity:`	`critical` / `high` / `medium` / `low` / `informational` (alias `sev:`)
`risk_score`	Numeric comparison on the Elastic risk score (0 to 100): `risk_score>50`, `risk_score<=20`, `risk_score=99` (alias `risk`; Elastic rules only)
`stages:`	Rules with exactly N pipeline stages
`correlation:`	`single_event` / `sequence` / `alternatives` / `alternatives_cross_log` / `all_required` / `correlated`
`with:`	Co-occurrence event-id; stacks (`with:4624 with:4769`) to require all, while a comma list in one occurrence (`with:4624,4769`) is an either-or group. Implies multi-event
`like:`	Structural neighbors of a rule slug (equivalents + subsumption stricter / broader): `like:comsvcs_lsass_memory_dump-splunk-sysmon`
`groupby:`	Entity-grouping substring match against `group_by_keys`: `groupby:user`, `groupby:host`
`uses:`	Rules whose predicate tree touches the field (any kind, any value): `uses:CommandLine`
`excludes:`	Rules with top-level `not()` clauses on the field (FP whitelists): `excludes:ParentImage`
`field:` / `value:`	Predicate search; narrows rule cards to those with a matching leaf and drives the indicator tier. Unquoted = substring, wildcards allowed (`value:mimikatz`)
`indicator:`	Shorthand for `field:F value:V`: `indicator:Image=*\powershell.exe`
`kind:`	Filter by predicate kind. Narrows rule cards to those carrying a matching predicate leaf (`vendor:elastic kind:cidr_match`) and drives the indicator tier: `contains` / `starts_with` / `ends_with` / `regex` / `cidr` / `eq` / `in` … (operator aliases `op:`/`match:`)
`has:` / `no:`	`sample`, `field`, `notes`, `refs`, `trace`, `thirdparty`, `rule`, `pattern`, `timewindow`, `threshold`, `newterms`, `sigma`/`elastic`/`splunk`/`kusto`/`chronicle`
`-op:val`	Exclude matches; works on most operators but not `type:`/`like:`/`has:`/`no:` (use `no:<flag>` to exclude a rule flag): `tactic:execution -vendor:splunk`. Standalone `-kind:`/`-field:`/`-value:` drop every rule carrying a matching predicate leaf (`type:rules -kind:is_null`)
`field:"…"` / `value:"…"`	Quoted value = anchored exact match (also allows spaces): `value:"net user"`
`a,b`	Comma = OR inside one operator (`vendor:sigma,elastic`, `severity:high,critical`); repeating a facet merges the same way. `field:`/`value:` never split (literal commas)
`vendors:` / `stage:`	Singular and plural spellings fold to the canonical operator and value: `tactics:` = `tactic:`, `type:event` = `type:events`, `correlation:sequences` = `correlation:sequence`, `has:thresholds` = `has:threshold`
`"quoted phrase"`	Exact-match a multi-word phrase (free text)

Invoke-Obfuscation CLIP+ Launcher

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: `condition`

Stage 1: `selection`

Indicators

Keyboard shortcuts

Search operators

Invoke-Obfuscation CLIP+ Launcher

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: condition

Stage 1: selection

Indicators

Stage 0: `condition`

Stage 1: `selection`