CVE-2025-65108 is a critical-severity (CVSS 10) Code Injection vulnerability in md-to-pdf. A fix is available for md-to-pdf — see the affected versions and patch details below.
md-to-pdf is vulnerable to arbitrary JavaScript code execution when parsing front matter
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.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- 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-2025-65108.
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-2025-65108 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 378,567 CVEs with a current EPSS score, this one falls in the < 10% 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.
md-to-pdfnpmDescription
Summary
A Markdown front-matter block that contains JavaScript delimiter causes the JS engine in gray-matter library to execute arbitrary code in the Markdown to PDF converter process of md-to-pdf library, resulting in remote code execution.
Details
md-to-pdf uses the gray-matter library to parse front-matter. Gray-matter exposes a JavaScript engine that, when enabled or triggered by certain front-matter delimiters (e.g. ---js or ---javascript), will evaluate the front-matter contents as JavaScript. If user-supplied Markdown is fed to md-to-pdf and the front-matter contains malicious JS, the converter process will execute that code.
PoC
const { mdToPdf } = require('md-to-pdf');
var payload = '---javascript\n((require("child_process")).execSync("calc.exe"))\n---RCE';
(async () => {
await mdToPdf({ content: payload }, { dest: './output.pdf'});
})();
Running the PoC on Windows launches the calculator application, demonstrating arbitrary code execution.
Impact
- Remote code execution in the process that performs Markdown->PDF conversion.
- If the converter is run in a web app or cloud service, an attacker uploading malicious Markdown can execute arbitrary commands on the
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | md-to-pdf | all versions | 5.2.5npm install md-to-pdf@5.2.5 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for md-to-pdf, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update md-to-pdf to 5.2.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-65108 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-2025-65108 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-65108. 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-2025-65108 in your dependencies?
O3 Security finds CVE-2025-65108 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.