GHSA-px4h-xg32-q955 is a high-severity (CVSS 7.5) CWE-1333 vulnerability in normalize-url. O3 Security confirms whether GHSA-px4h-xg32-q955 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
ReDoS in normalize-url
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
normalize-urlnpmDescription
The normalize-url package before 4.5.1, 5.x before 5.3.1, and 6.x before 6.0.1 for Node.js has a ReDoS (regular expression denial of service) issue because it has exponential performance for data: URLs.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | normalize-url | ≥ 4.3.0&&< 4.5.1 | 4.5.1 |
| 📦npm | normalize-url | ≥ 5.0.0&&< 5.3.1 | 5.3.1 |
| 📦npm | normalize-url | ≥ 6.0.0&&< 6.0.1 | 6.0.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for normalize-url. 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 normalize-url to 4.5.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-px4h-xg32-q955 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-px4h-xg32-q955 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-px4h-xg32-q955. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Frequently Asked Questions
Is GHSA-px4h-xg32-q955 in your dependencies?
O3 detects GHSA-px4h-xg32-q955 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.