CVE-2026-63220 is a medium-severity (CVSS 4.8) CWE-348 vulnerability in codeigniter4/framework. A fix is available for codeigniter4/framework — see the affected versions and patch details below.
CodeIgniter: Spoofable forwarded HTTPS headers in IncomingRequest::isSecure()
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-63220.
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.
How urgent is this, really
CVE-2026-63220 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
codeigniter4/frameworkReal-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
IncomingRequest::isSecure() trusted the X-Forwarded-Proto and Front-End-Https headers from any incoming request. In affected deployments, an attacker could spoof these headers and cause the application to incorrectly treat an HTTP request as secure.
This may impact applications that rely on isSecure(), force_https(), forceGlobalSecureRequests, or similar logic to enforce HTTPS-only access or make security-sensitive decisions.
Exploitability depends on deployment configuration. Applications are most exposed if the backend is reachable directly over HTTP, or if a reverse proxy/load balancer forwards client-supplied forwarding headers without stripping or overwriting them.
Patches
Upgrade to v4.7.4 or later.
Workarounds
Users who cannot upgrade immediately should enforce HTTP-to-HTTPS redirects outside CodeIgniter, for example with Apache .htaccess/virtual host rules, nginx server blocks, Caddy site config, or load balancer redirect rules.
Users should also ensure that reverse proxies strip or overwrite client-supplied X-Forwarded-Proto and Front-End-Https headers before forwarding requests to the application.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | codeigniter4/framework | all versions | 4.7.4composer require codeigniter4/framework:^4.7.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for codeigniter4/framework, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update codeigniter4/framework to 4.7.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-63220 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-63220 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-63220. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-63220 in your dependencies?
O3 Security finds CVE-2026-63220 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.