GHSA-87pf-7x99-5xc4
MEDIUMSilverstripe Hostname, IP and Protocol Spoofing through HTTP Headers
Blast Radius
silverstripe/framework🐘silverstripe/framework🐘silverstripe/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
In it's default configuration, SilverStripe trusts all originating IPs to include HTTP headers for Hostname, IP and Protocol. This enables reverse proxies to forward requests while still retaining the original request information. Trusted IPs can be limited via the SS_TRUSTED_PROXY_IPS constant. Even with this restriction in place, SilverStripe trusts a variety of HTTP headers due to different proxy notations (e.g. X-Forwarded-For vs. Client-IP). Unless a proxy explicitly unsets invalid HTTP headers from connecting clients, this can lead to spoofing requests being passed through trusted proxies.
The impact of spoofed headers can include Director::forceSSL() not being enforced, SS_HTTPRequest->getIP() returning a wrong IP (disabling any IP restrictions), and spoofed hostnames circumventing any hostname-specific restrictions enforced in SilverStripe Controllers.
Regardless on running a reverse proxy in your hosting infrastructure, please follow the instructions on Secure Coding: Request hostname forgery in order to opt-in to these protections. If your website is not behind a reverse proxy, you might already be protected if using Apache with mod_env enabled, and you have the following line in your .htaccess file: SetEnv BlockUntrustedIPs true.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | silverstripe/framework | all versions | 3.1.17 |
| 🐘Packagist | silverstripe/framework | ≥ 3.2.0&&< 3.2.2 | 3.2.2 |
| 🐘Packagist | silverstripe/framework | ≥ 3.3.0-beta1&&< 3.3.0 | 3.3.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for silverstripe/framework. 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 silverstripe/framework to 3.1.17 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-87pf-7x99-5xc4 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-87pf-7x99-5xc4 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-87pf-7x99-5xc4. 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-87pf-7x99-5xc4 in your dependencies?
O3 detects GHSA-87pf-7x99-5xc4 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.