CVE-2017-9303 — laravel/laravel
MEDIUMCVE-2017-9303 is a medium-severity (CVSS 6.1) Improper Input Validation vulnerability in laravel/laravel. A fix is available for laravel/laravel — see the affected versions and patch details below.
Laravel does not properly constrain the host portion of a password-reset URL
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-2017-9303 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 377,166 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
laravel/laravel🐘illuminate/auth🐘illuminate/auth🐘laravel/framework🐘laravel/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
Laravel 5.4.x before 5.4.22 does not properly constrain the host portion of a password-reset URL, which makes it easier for remote attackers to conduct phishing attacks by specifying an attacker-controlled host.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | laravel/laravel | ≥ 5.4.0&&< 5.4.22 | 5.4.22composer require laravel/laravel:^5.4.22 |
| 🐘Packagist | illuminate/auth | ≥ 5.3.0 | No fix |
| 🐘Packagist | illuminate/auth | ≥ 5.4.0&&< 5.4.22 | 5.4.22composer require illuminate/auth:^5.4.22 |
| 🐘Packagist | laravel/framework | ≥ 5.3.0 | No fix |
| 🐘Packagist | laravel/framework | ≥ 5.4.0&&< 5.4.22 | 5.4.22composer require laravel/framework:^5.4.22 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for laravel/laravel, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update laravel/laravel to 5.4.22 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2017-9303 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-2017-9303 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2017-9303. 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-2017-9303 in your dependencies?
O3 Security finds CVE-2017-9303 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.