GHSA-5hm8-vh6r-2cjq
MEDIUMCodeIgniter Shield Vulnerable to SameSite Attackers Bypassing the CSRF Protection
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
codeigniter4/shieldReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Impact
This vulnerability may allow SameSite Attackers to bypass the CodeIgniter4 CSRF protection 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/).
This vulnerability exists whether Config\Security::$csrfProtection is 'cookie' or 'session'.
It is also exploitable whether Config\Security::$regenerate is true or false.
Patches
Upgrade to CodeIgniter v4.2.3 or later and Shield v1.0.0-beta.2 or later.
Workarounds
Do all of the following:
- set
Config\Security::$csrfProtectionto'session' - remove old session data right after login (immediately after ID and password match)
- regenerate CSRF token right after login (immediately after ID and password match)
References
For more information
If you have any questions or comments about this advisory:
- Open an issue or discussion in codeigniter4/shield
- Email us at [email protected]
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | codeigniter4/shield | ≥ 1.0.0-beta&&< 1.0.0-beta.2 | 1.0.0-beta.2 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for codeigniter4/shield. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update codeigniter4/shield to 1.0.0-beta.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-5hm8-vh6r-2cjq is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-5hm8-vh6r-2cjq is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-5hm8-vh6r-2cjq. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-5hm8-vh6r-2cjq in your dependencies?
O3 detects GHSA-5hm8-vh6r-2cjq across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.