Pysa¶

The Python Static Analyzer Pysa performs taint analysis to identify potential security problems. Pysa traces data streams from their origin to their endpoint and identifies vulnerable code.

Configuration¶

Pysa uses two file types for configuration:

a taint.config file in JSON format, in which sources, sinks, features and rules are defined.

{
  "comment": "UserControlled, Test, Demo sources are predefined. Same for Demo, Test and RemoteCodeExecution sinks",
  "sources": [],
  "sinks": [],
  "features": [],
  "rules": []
}

files with the extension .pysa in a directory configured with taint_models_path in your .pyre_configuration file.

You can find practical examples in the Pyre repository.

Use¶

Pyre can be called, for example with

$ $ uv run pyre analyze --save-results-to ./

The --save-results-to option stores detailed results in ./taint-output.json.

Pysa postprocessor¶

Installation¶

$ uv add fb-sapp

Use¶

Parsing the JSON file, for example with
```
$ uv run sapp --database-name sapp.db analyze ./taint-output.json
```
The results are stored in the local SQLite file sapp.db.
Exploring the problems with
```
$ uv run sapp --database-name sapp.db explore
```
This starts an IPython interface connected to the SQLite database:

issues
lists all issues

issue 1
selects the first issue

trace
shows the data flow from source to sink

n
jumps to the next call

list
shows the source code of the call

jump 1
jumps to the first call and shows the source code

Further commands can be found in the SAPP Command-Line Interface.