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
Easy integration 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

Changelog

0.6.2 – 2019-03-05

This release brings Embark native support, fixes several bugs, and improves slither-check-upgradeability.

Added

Embark support (see the documentation) (#196)
Support for Solidity selector keyword (605ea7f)
--truffle-build-directory flag to support custom build directory (#187)

Changed

Rename slither-check-upgradability to slither-check-upgradeability (bffa59f)
--ignore-truffle-compile flag renamed to --truffle-ignore-compile
Improve slither-check-upgradeability output and documentation.
API changed: Add framework detection within Slither object; the caller does not need to check for native/truffle/embark (ee1b4c2)

Fixed

Incorrect source mapping computation (#194)
Incorrect data dependency for return values (#193)
Crash related to the support of abi.decode (#177)

Install

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

Using Pip

$ pip install slither-analyzer

Using Git

$ git clone https://github.com/trailofbits/slither.git && cd slither
$ python setup.py install

Use

Run Slither on a Truffle application:

slither .

Run Slither on a single file:

$ slither tests/uninitialized.sol 
[..]
INFO:Detectors:
Uninitialized.destination (tests/uninitialized.sol#5) is never initialized. It is used in:
	- transfer (tests/uninitialized.sol#7-9)
Reference: https://github.com/trailofbits/slither/wiki/Vulnerabilities-Description#uninitialized-state-variables
[..]

Slither can be run on:

A .sol file
A Truffle directory
A directory containing *.sol files (all the *.sol files will be analyzed)
A glob (be sure to quote the argument when using a glob)

Configuration

--solc SOLC: Path to solc (default ‘solc’)
--solc-args SOLC_ARGS: Add custom solc arguments. SOLC_ARGS can contain multiple arguments
--disable-solc-warnings: Do not print solc warnings
--solc-ast: Use the solc AST file as input (solc file.sol --ast-json > file.ast.json)
--json FILE: Export results as JSON

Detectors

By default, all the detectors are run.

Num	Detector	What it Detects	Impact	Confidence
1	`suicidal`	Functions allowing anyone to destruct the contract	High	High
2	`uninitialized-local`	Uninitialized local variables	High	High
3	`uninitialized-state`	Uninitialized state variables	High	High
4	`uninitialized-storage`	Uninitialized storage variables	High	High
5	`arbitrary-send`	Functions that send ether to arbitrary destinations	High	Medium
6	`controlled-delegatecall`	Controlled delegatecall destination	High	Medium
7	`reentrancy`	Reentrancy vulnerabilities	High	Medium
8	`locked-ether`	Contracts that lock ether	Medium	High
9	`const-func`	Constant functions changing the state	Medium	Medium
10	`tx-origin`	Dangerous usage of `tx.origin`	Medium	Medium
11	`assembly`	Assembly usage	Informational	High
12	`constable-states`	State variables that could be declared constant	Informational	High
13	`external-function`	Public function that could be declared as external	Informational	High
14	`low-level-calls`	Low level calls	Informational	High
15	`naming-convention`	Conformance to Solidity naming conventions	Informational	High
16	`pragma`	If different pragma directives are used	Informational	High
17	`solc-version`	Old versions of Solidity (< 0.4.23)	Informational	High
18	`unused-state`	Unused state variables

Printers

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

Num	Printer	Description
1	`call-graph`	Export the call-graph of the contracts to a dot file
2	`contract-summary`	Print a summary of the contracts
3	`function-summary`	Print a summary of the functions
4	`human-summary`	Print a human-readable summary of the contracts
5	`inheritance`	Print the inheritance relations between contracts
6	`inheritance-graph`	Export the inheritance graph of each contract to a dot file
7	`slithir`	Print the slithIR representation of the functions
8	`vars-and-auth`	Print the state variables written and the authorization of the functions

Penetration Testing

slither v0.6.2 releases: Static Analyzer for Solidity