CVE-2024-4367 is a medium-severity (CVSS 5.6) CWE-754 vulnerability in pdfjs-dist. 17 public exploit references exist, so weaponization risk is real. A fix is available for pdfjs-dist — see the affected versions and patch details below.
PDF.js vulnerable to arbitrary JavaScript execution upon opening a malicious PDF
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-4367.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2024-4367 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the 50–90% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
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.
pdfjs-distnpmDescription
Impact
If pdf.js is used to load a malicious PDF, and PDF.js is configured with isEvalSupported set to true (which is the default value), unrestricted attacker-controlled JavaScript will be executed in the context of the hosting domain.
Patches
The patch removes the use of eval:
https://github.com/mozilla/pdf.js/pull/18015
Workarounds
Set the option isEvalSupported to false.
References
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | pdfjs-dist | all versions | 4.2.67npm install pdfjs-dist@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, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2024-4367 can be triaged on real exposure rather than presence alone.
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.
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.
Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux 7 | firefox-0:115.11.0-1.el7_9 | RHSA-2024:2881 |
| Red Hat Enterprise Linux 7 | thunderbird-0:115.11.0-1.el7_9 | RHSA-2024:2913 |
| Red Hat Enterprise Linux 7 Extended Lifecycle Support | webkitgtk4-0:2.52.5-1.el7_9 | RHSA-2026:58564 |
| Red Hat Enterprise Linux 8 | firefox-0:115.11.0-1.el8_10 | RHSA-2024:3783 |
| Red Hat Enterprise Linux 8 | thunderbird-0:115.11.0-1.el8_10 | RHSA-2024:3784 |
| Red Hat Enterprise Linux 8 | webkit2gtk3-0:2.52.5-1.el8_10 | RHSA-2026:42088 |
| Red Hat Enterprise Linux 8.2 Advanced Update Support | firefox-0:115.11.0-1.el8_2 | RHSA-2024:2882 |
| Red Hat Enterprise Linux 8.2 Advanced Update Support | thunderbird-0:115.11.0-1.el8_2 | RHSA-2024:3338 |
Frequently Asked Questions
Is CVE-2024-4367 in your dependencies?
O3 Security finds CVE-2024-4367 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.