Codeigniter Cross-Site Request Forgery

Shield is an authentication and authorization framework for CodeIgniter 4. This vulnerability may allow [SameSite Attackers](https://canitakeyoursubdomain.name/) to bypass the [CodeIgniter4 CSRF protection](https://codeigniter4.github.io/userguide/libraries/security.html) mechanism with CodeIgniter Shield. For this attack to succeed, the attacker must have direct (or indirect, e.g., XSS) control over a subdomain site (e.g., `https://a.example.com/`) of the target site (e.g., `http://example.com/`). Upgrade to **CodeIgniter v4.2.3 or later** and **Shield v1.0.0-beta.2 or later**. As a workaround: set `Config\Security::$csrfProtection` to `'session,'`remove old session data right after login (immediately after ID and password match) and regenerate CSRF token right after login (immediately after ID and password match) (2022-08-12, CVE-2022-35943)

CodeIgniter4 is the 4.x branch of CodeIgniter, a PHP full-stack web framework. A vulnerability in versions prior to 4.1.9 might allow remote attackers to bypass the CodeIgniter4 Cross-Site Request Forgery (CSRF) protection mechanism. Users should upgrade to version 4.1.9. There are workarounds for this vulnerability, but users will still need to code as these after upgrading to v4.1.9. Otherwise, the CSRF protection may be bypassed. If auto-routing is enabled, check the request method in the controller method before processing. If auto-routing is disabled, either avoid using `$routes->add()` and instead use HTTP verbs in routes; or check the request method in the controller method before processing. (2022-02-28, CVE-2022-24712)

The absence of Anti-CSRF tokens may lead to a Cross-Site Request Forgery attack that can result in executing a specific application action as another logged in user, e.g. steal their account by changing their email and password or silently adding a new admin user account when executed from the administrator account.

The attacker may copy one of your web application forms, e.g. email/password change form.

The webpage will contain a form with the exact set of fields as the original application but with input values already provided and the submit button replaced with a Javascript code causing auto-submission. When the page is accessed the form will be immediately submitted and page contents replaced with a valid content or a redirect to your original application.

One of your application users who is already logged in can be then tricked to navigate to such malicious page e.g. by clicking a link in a phishing email, and the pre-populated form content will be submitted to your application like it would be submitted by your user.