title: SameSite may allow cross-site request forgery (CSRF) protection to be bypassed
description: 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)
problem types: CWE-352: Cross-Site Request Forgery (CSRF)
affected:
{
product: shield
vendor: codeigniter4
versions:
status: affected, version: > 4.3.2, > v1.0.0-beta.2
}
metrics:
cvssV3_1: [
attackComplexity: HIGH
attackVector: NETWORK
availabilityImpact: LOW
baseScore: 5.9
baseSeverity: MEDIUM
confidentialityImpact: NONE
integrityImpact: HIGH
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: REQUIRED
vectorString: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:L
version: 3.1
]