GHSA-fq4p-86hh-42v9
MEDIUMZend-Diactoros URL Rewrite vulnerability
Blast Radius
zendframework/zend-diactorosReal-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
zend-diactoros (and, by extension, Expressive), zend-http (and, by extension, Zend Framework MVC projects), and zend-feed (specifically, its PubSubHubbub sub-component) each contain a potential URL rewrite exploit. In each case, marshaling a request URI includes logic that introspects HTTP request headers that are specific to a given server-side URL rewrite mechanism.
When these headers are present on systems not running the specific URL rewriting mechanism, the logic would still trigger, allowing a malicious client or proxy to emulate the headers to request arbitrary content.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | zendframework/zend-diactoros | ≥ 1.0.0&&< 1.8.4 | 1.8.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for zendframework/zend-diactoros. 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 zendframework/zend-diactoros to 1.8.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-fq4p-86hh-42v9 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-fq4p-86hh-42v9 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-fq4p-86hh-42v9. 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-fq4p-86hh-42v9 in your dependencies?
O3 detects GHSA-fq4p-86hh-42v9 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.