Sigma Command Line Interface

This is the Sigma command line interface using the pySigma library to manage, list and convert Sigma rules into query languages.

Getting Started

Installation

The easiest way to install the Sigma CLI is via pipx or pip. For this purpose run one of the following:

python -m pipx install sigma-cli
python -m pip install sigma-cli

on macOS use

python3 -m pip install sigma-cli

brew install sigma-cli

Another way is to run this from source in a virtual environment managed by Poetry:

git clone https://github.com/SigmaHQ/sigma-cli.git
cd sigma-cli
poetry install
poetry shell

Usage

The CLI is available as sigma command. A typical invocation is:

sigma convert -t <backend> -p <processing pipeline 1> -p <processing pipeline 2> [...] <directory or file>

E.g. to convert process creation Sigma rules from a directory into Splunk queries for Sysmon logs run:

sigma convert -t splunk -p sysmon sigma/rules/windows/process_creation

Required backends must be installed using the following command prior to conducting conversions.

To list all available plugins run the following command:

sigma plugin list

Install a plugin of your choice with:

sigma plugin install <backend>

E.g. to install the splunk backend run:

sigma plugin install splunk

Available conversion backends and processing pipelines can be listed with sigma list. Use -O or --backend-option for passing options to the backend as key=value pairs (-O testparam=123) . This backend option parameter can be used multiple times (-O first=123 -O second=456).

Backends can support different output formats, e.g. plain queries and a file that can be imported into the target system. These formats can be listed with sigma list formats <backend> and specified for conversion with the -f option.

In addition, an output file can be specified with -o.

Example for output formats and files:

sigma convert -t splunk -f savedsearches -p sysmon -o savedsearches.conf sigma/rules/windows/process_creation

Outputs a Splunk savedsearches.conf containing the converted searches.

Separate File Output

For scenarios where you need to convert multiple rules into separate files (e.g., for version control or selective deployment), use the --output-dir parameter along with --output-filename-template:

sigma convert -t esql -p ecs_windows --output-dir translated_rules/ rules/

This will create a separate file for each converted rule in the translated_rules/ directory.

Template Variables:

The --output-filename-template parameter accepts the following variables:

• {path}: Relative source directory path (e.g., windows for rules/windows/rule.yml)
• {stem}: Filename without extension (e.g., rule for rule.yml)
• {index}: Query index for rules that generate multiple queries (empty if only one query)

Examples:

Flat output structure (all files in one directory):

sigma convert -t esql -p ecs_windows --output-dir translated/ --output-filename-template "{stem}.esql" rules/

Preserve directory structure:

sigma convert -t esql -p ecs_windows --output-dir translated/ --output-filename-template "{path}/{stem}.esql" rules/

Handle rules with multiple queries:

sigma convert -t esql -p ecs_windows --output-dir translated/ --output-filename-template "{stem}-{index}.esql" rules/

Given input structure:

rules/
├── windows/
│   └── rule_1.yml
├── linux/
│   └── rule_2.yml

With --output-filename-template "{path}/{stem}.esql", the output will be:

translated/
├── windows/
│   └── rule_1.esql
├── linux/
│   └── rule_2.esql

Integration of Backends and Pipelines

Sigma CLI automatically discovers installed pySigma backend and processing pipeline plugins. Install the plugin package in the same Python environment as Sigma CLI. For plugins listed by sigma plugin list, use sigma plugin install <identifier>.

For a custom plugin package, use the command matching your Sigma CLI installation:

# Sigma CLI installed with pip
python -m pip install <package-name>

# Sigma CLI installed with pipx
pipx inject sigma-cli <package-name>

# Sigma CLI source checkout managed by Poetry
poetry add <package-name>

Custom plugins provide backend classes under the sigma.backends namespace and processing pipeline factories under the sigma.pipelines namespace. See the pySigma plugin guide for the package layout and exports. No changes to Sigma CLI's source files are needed.

After installation, use sigma list targets and sigma list pipelines to find the identifiers accepted by sigma convert -t and -p. Use sigma list formats <backend> to list the backend's output formats for -f.

Maintainers

The project is currently maintained by:

• Thomas Patzke [email protected]