Installation of WSL Kali-Linux

Status: experimental
Severity: high
Log source: product windows, category process_creation
Author: Swachchhanda Shrawan Poudel (Nextron Systems)
Source: github.com/SigmaHQ/sigma

Detects installation of Kali Linux distribution through Windows Subsystem for Linux (WSL). Attackers may use Kali Linux WSL to leverage its penetration testing tools and capabilities for malicious purposes.

MITRE ATT&CK coverage

Tactic	Techniques
Execution	`T1059` Command and Scripting Interpreter

Event coverage

Provider	Event	Title
Sysmon	Event ID 1	Process creation

Rule body yaml

title: Installation of WSL Kali-Linux
id: eca8ae39-5c3c-4321-b538-9e64fe25822e
status: experimental
description: |
    Detects installation of Kali Linux distribution through Windows Subsystem for Linux (WSL).
    Attackers may use Kali Linux WSL to leverage its penetration testing tools and capabilities for malicious purposes.
references:
    - https://medium.com/@redfanatic7/running-kali-linux-on-windows-51ad95166e6e
    - https://learn.microsoft.com/en-us/windows/wsl/install
author: Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2025-10-10
tags:
    - attack.execution
    - attack.t1059
logsource:
    category: process_creation
    product: windows
detection:
    selection_wsl_img:
        - Image|endswith: '\wsl.exe'
        - OriginalFileName: 'wsl'
    selection_wsl_install:
        CommandLine|contains:
            - ' --install '
            - ' -i '
    selection_wsl_kali:
        CommandLine|contains: 'kali'
    condition: all of selection_wsl_*
falsepositives:
    - Legitimate installation or usage of Kali Linux WSL by administrators or security teams
level: high

Stages and Predicates

Stage 0: `condition`

all of selection_wsl_*

Stage 1: `selection_wsl_img`

selection_wsl_img:
    - Image|endswith: '\wsl.exe'
    - OriginalFileName: 'wsl'

Stage 2: `selection_wsl_install`

selection_wsl_install:
    CommandLine|contains:
        - ' --install '
        - ' -i '

Stage 3: `selection_wsl_kali`

selection_wsl_kali:
    CommandLine|contains: 'kali'

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	`--install` `-i` corpus 4 (sigma 4) `kali`
`Image`	ends_with	`\wsl.exe` corpus 11 (sigma 11)
`OriginalFileName`	eq	`wsl`

`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)

Installation of WSL Kali-Linux

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: `condition`

Stage 1: `selection_wsl_img`

Stage 2: `selection_wsl_install`

Stage 3: `selection_wsl_kali`

Indicators

Keyboard shortcuts

Search operators

Installation of WSL Kali-Linux

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: condition

Stage 1: selection_wsl_img

Stage 2: selection_wsl_install

Stage 3: selection_wsl_kali

Indicators

Stage 0: `condition`

Stage 1: `selection_wsl_img`

Stage 2: `selection_wsl_install`

Stage 3: `selection_wsl_kali`