CVE-2026-33732 is a medium-severity (CVSS 4.8) CWE-706 vulnerability in srvx. O3 Security confirms whether CVE-2026-33732 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
srvx is vulnerable to middleware bypass via absolute URI in request line
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, a proxy for how much of the ecosystem is exposed.
srvxnpmDescription
srvx is a universal server based on web standards. Prior to version 0.11.13, a pathname parsing discrepancy in srvx's FastURL allows middleware bypass on the Node.js adapter when a raw HTTP request uses an absolute URI with a non-standard scheme (e.g. file://). Starting in version 0.11.13, the FastURL constructor now deopts to native URL for any string not starting with /, ensuring consistent pathname resolution.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | srvx | all versions | 0.11.13 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for srvx. 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 srvx to 0.11.13 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-33732 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 CVE-2026-33732 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 CVE-2026-33732. 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-2026-33732 in your dependencies?
O3 detects CVE-2026-33732 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.