smbexec.py Service Installation

Status: test
Severity: high
Log source: product windows, service system
Author: Omer Faruk Celik
Source: github.com/SigmaHQ/sigma

Detects the use of smbexec.py tool by detecting a specific service installation

MITRE ATT&CK coverage

Tactic	Techniques
Execution	`T1569.002` System Services: Service Execution
Lateral Movement	`T1021.002` Remote Services: SMB/Windows Admin Shares

Event coverage

Provider	Event
Service-Control-Manager	Event ID 7045

Rule body yaml

title: smbexec.py Service Installation
id: 52a85084-6989-40c3-8f32-091e12e13f09
status: test
description: Detects the use of smbexec.py tool by detecting a specific service installation
references:
    - https://blog.ropnop.com/using-credentials-to-own-windows-boxes-part-2-psexec-and-services/
    - https://github.com/fortra/impacket/blob/33058eb2fde6976ea62e04bc7d6b629d64d44712/examples/smbexec.py#L286-L296
    - https://github.com/fortra/impacket/blob/edef71f17bc1240f9f8c957bbda98662951ac3ec/examples/smbexec.py#L60 # Old service name
author: Omer Faruk Celik
date: 2018-03-20
modified: 2023-11-09
tags:
    - attack.lateral-movement
    - attack.execution
    - attack.t1021.002
    - attack.t1569.002
logsource:
    product: windows
    service: system
detection:
    selection_eid:
        Provider_Name: 'Service Control Manager'
        EventID: 7045
    selection_service_name:
        ServiceName: 'BTOBTO'
    selection_service_image:
        ImagePath|contains:
            - '.bat & del '
            - '__output 2^>^&1 >'
    condition: selection_eid and 1 of selection_service_*
falsepositives:
    - Unknown
level: high

Stages and Predicates

Stage 0: `condition`

selection_eid and 1 of selection_service_*

Stage 1: `selection_eid`

selection_eid:
    Provider_Name: 'Service Control Manager'
    EventID: 7045

Stage 2: `selection_service_name`

selection_service_name:
    ServiceName: 'BTOBTO'

Stage 3: `selection_service_image`

selection_service_image:
    ImagePath|contains:
        - '.bat & del '
        - '__output 2^>^&1 >'

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
`ImagePath`	match	`.bat & del` `__output 2^>^&1 >`
`Provider_Name`	eq	`Service Control Manager` corpus 50 (sigma 50)
`ServiceName`	eq	`BTOBTO` corpus 2 (sigma 2)

`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)

smbexec.py Service Installation

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: `condition`

Stage 1: `selection_eid`

Stage 2: `selection_service_name`

Stage 3: `selection_service_image`

Indicators

Keyboard shortcuts

Search operators

smbexec.py Service Installation

MITRE ATT&CK coverage

Event coverage

Rule body yaml

Stages and Predicates

Stage 0: condition

Stage 1: selection_eid

Stage 2: selection_service_name

Stage 3: selection_service_image

Indicators

Stage 0: `condition`

Stage 1: `selection_eid`

Stage 2: `selection_service_name`

Stage 3: `selection_service_image`