Slither, the Solidity source analyzer

Slither is a Solidity static analysis framework written in Python 3. It runs a suite of vulnerability detectors, prints visual information about contract details, and provides an API to easily write custom analyses. Slither enables developers to find vulnerabilities, enhance their code comprehension, and quickly prototype custom analyses.

Features

• Detects vulnerable Solidity code with low false positives
• Identifies where the error condition occurs in the source code
• Easily integrates into continuous integration and Truffle builds
• Built-in 'printers' quickly report crucial contract information
• Detector API to write custom analyses in Python
• Ability to analyze contracts written with Solidity >= 0.4
• Intermediate representation (SlithIR) enables simple, high-precision analyses
• Correctly parses 99.9% of all public Solidity code
• Average execution time of less than 1 second per contract

Bugs and Optimizations Detection

Run Slither on a Truffle/Embark/Dapp/Etherlime application:

slither .

Run Slither on a single file:

$ slither tests/uninitialized.sol

For additional configuration, see the usage documentation.

Use solc-select if your contracts require older versions of solc.

Detectors

Slither has more than 30 public detectors, including:

• shadowing-state: State variables shadowing
• reentrancy-eth: Reentrancy vulnerabilities
• erc20-interface: Incorrect ERC20 interfaces
• incorrect-equality: Dangerous strict equalities
• constable-states: State variables that could be declared constant

See the Detectors Documentation for the complete list. By default, all the detectors are run.

Check out Crytic to get access to additional Slither's detectors and GitHub integration.

Printers

Quick Review Printers

• human-summary: Print a human-readable summary of the contracts
• inheritance-graph: Export the inheritance graph of each contract to a dot file
• contract-summary: Print a summary of the contracts

In-Depth Review Printers

• call-graph: Export the call-graph of the contracts to a dot file
• cfg: Export the CFG of each functions
• function-summary: Print a summary of the functions
• vars-and-auth: Print the state variables written and the authorization of the functions

To run a printer, use --print and a comma-separated list of printers.

See the Printer documentation for the complete lists.

Tools

• slither-check-upgradeability: Review delegatecall-based upgradeability
• slither-flat: Flatten a codebase
• slither-erc: Check the ERC's conformance
• slither-format: Automatic patches generation

See the Tool documentation for additional tools.

Contact us to get help on building custom tools.

How to install

Slither requires Python 3.6+ and solc, the Solidity compiler.

Using Pip

$ pip3 install slither-analyzer

Using Git

$ git clone https://github.com/crytic/slither.git && cd slither
$ python3 setup.py install

We recommend using an Python virtual environment, as detailed in the Developer Installation Instructions, if you prefer to install Slither via git.

Using Docker

Use the eth-security-toolbox docker image. It includes all of our security tools and every major version of Solidity in a single image. /home/share will be mounted to /share in the container.

docker pull trailofbits/eth-security-toolbox

To share a directory in the container:

docker run -it -v /home/share:/share trailofbits/eth-security-toolbox

Getting Help

Feel free to stop by our Slack channel (#ethereum) for help using or extending Slither.

• The Printer documentation describes the information Slither is capable of visualizing for each contract.

• The Detector documentation describes how to write a new vulnerability analyses.

• The API documentation describes the methods and objects available for custom analyses.

• The SlithIR documentation describes the SlithIR intermediate representation.

License

Slither is licensed and distributed under the AGPLv3 license. Contact us if you're looking for an exception to the terms.

Publication

• Slither: A Static Analysis Framework For Smart Contracts, Josselin Feist, Gustavo Grieco, Alex Groce - WETSEB '19

If you are using Slither on an academic work, consider applying to the Crytic $10k Research Prize.