CVE-2021-21239 PoC — Open default xmlsec1 key-type preference

Source

https://github.com/GrantBirki/redash-vulnerable

Associated Vulnerability

Title: Open default xmlsec1 key-type preference (CVE-2021-21239)
Description:PySAML2 is a pure python implementation of SAML Version 2 Standard. PySAML2 before 6.5.0 has an improper verification of cryptographic signature vulnerability. Users of pysaml2 that use the default CryptoBackendXmlSec1 backend and need to verify signed SAML documents are impacted. PySAML2 does not ensure that a signed SAML document is correctly signed. The default CryptoBackendXmlSec1 backend is using the xmlsec1 binary to verify the signature of signed SAML documents, but by default xmlsec1 accepts any type of key found within the given document. xmlsec1 needs to be configured explicitly to only use only _x509 certificates_ for the verification process of the SAML document signature. This is fixed in PySAML2 6.5.0.

Description

A Dockerized Redash instance that is vulnerable to CVE-2021-21239

Readme

# redash-vulnerable 🐛

A Dockerized Redash instance that is vulnerable to [`CVE-2021-21239`](https://nvd.nist.gov/vuln/detail/CVE-2021-21239) as written about by [Calif](https://blog.calif.io/p/redash-saml-authentication-bypass).

## Usage 💻

### Starting the server (preserving data)

```bash
script/server
```

This will start the Redash server using Docker Compose in detached mode, preserving any existing data. The server will be available at [`http://localhost:8080`](http://localhost:8080/setup).

### Starting fresh (destroying all data)

```bash
script/server --destroy
```

This will destroy all existing containers, volumes, and data directories, then rebuild everything from scratch. Use this when you want to start completely fresh.

**Note:** The `--destroy` flag will permanently delete all your Redash data, including dashboards, queries, users, and database content.

File Snapshot

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