CVE-2024-4367
MEDIUMCVE-2024-4367 is a medium-severity (CVSS 5.6) CWE-754 vulnerability in pdfjs-dist. 16 public exploit references exist, so weaponization risk is real. O3 Security confirms whether CVE-2024-4367 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
PDF.js vulnerable to arbitrary JavaScript execution upon opening a malicious PDF
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.
pdfjs-distnpmDescription
A type check was missing when handling fonts in PDF.js, which would allow arbitrary JavaScript execution in the PDF.js context. This vulnerability affects Firefox < 126, Firefox ESR < 115.11, and Thunderbird < 115.11.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | pdfjs-dist | all versions | 4.2.67 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Firefox ESR 115.11 - PDF.js Arbitrary JavaScript execution
by Milad karimi · Apr 22, 2025
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pdfjs-dist. 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 pdfjs-dist to 4.2.67 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-4367 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-2024-4367 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-2024-4367. 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-2024-4367 in your dependencies?
O3 detects CVE-2024-4367 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.