CVE-2024-10491
MEDIUMCVE-2024-10491 is a medium-severity (CVSS 4) CWE-74 vulnerability in express. 1 public exploit reference exists, so weaponization risk is real. O3 Security confirms whether CVE-2024-10491 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Preload arbitrary resources by injecting additional `Link` headers
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
expressnpmDescription
A vulnerability has been identified in the Express response.links function, allowing for arbitrary resource injection in the Link header when unsanitized data is used.
The issue arises from improper sanitization in Link header values, which can allow a combination of characters like ,, ;, and <> to preload malicious resources.
This vulnerability is especially relevant for dynamic parameters.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | express | all versions | 4.0.0-rc1 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for express. 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 express to 4.0.0-rc1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-10491 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-2024-10491 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-2024-10491. 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-2024-10491 in your dependencies?
O3 detects CVE-2024-10491 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.