The popular open-source note-taking and to-do application, Joplin, is affected by a cross-site scripting (XSS) vulnerability that has been identified with the CVE identifier of CVE-2023-37299. This vulnerability affects Joplin versions before 2.11.5 and allows potential attackers to execute malicious code via an AREA element of an image map. In this post, we will delve into the details of this vulnerability, its impact, and the recommended mitigations for affected users.

Vulnerability Details

Joplin's XSS vulnerability lies in its handling of AREA elements in an image map. An attacker can craft a malicious note containing an image map with a carefully constructed AREA element to inject and execute arbitrary code on the victim's machine through the Joplin application. This particular vulnerability exposes the application's users to potential security risks if they import or view notes containing the malicious payloads.

An attacker can inject the following code snippet into a note within the Joplin application

<img src="image.jpg" usemap="#image-map">
<map name="image-map">
  <area href="javascript:alert('XSS');" shape="rect" coords=",,100,100">
</map>

This code snippet includes an image map (#image-map) associated with an image file (image.jpg). The AREA element within the map includes a JavaScript alert() function that displays an alert with the text "XSS." When a victim views the note containing this code snippet, the JavaScript payload executes, and the alert appears, demonstrating the XSS vulnerability.

Original References

This vulnerability was disclosed by the Joplin development team and has been assigned the CVE-2023-37299 identifier. The original references to this vulnerability can be found in the following links:

- Joplin GitHub Repository: https://github.com/laurent22/joplin
- CVE-2023-37299 in National Vulnerability Database (NVD): https://nvd.nist.gov/vuln/detail/CVE-2023-37299
- Joplin Release Notes for version 2.11.5: https://joplinapp.org/changelog/

Exploit Details

A potential attacker can exploit this vulnerability by crafting a note with a malicious payload, as shown in the code snippet above. The attacker then tricks a victim into importing or viewing the crafted note within Joplin. Once the payload is executed, the attacker gains access to sensitive information, such as credentials, and has control over the victim's Joplin environment.

The impact of this vulnerability depends on the level of access the attacker gains and the actions taken by the attacker after exploiting the vulnerability. To minimize risks, users should always be cautious when importing notes from unknown sources or viewing notes shared by untrusted parties.

Mitigations

To eliminate the risk of this vulnerability and protect users, the Joplin development team has released the version 2.11.5 update, which addresses and patches the XSS vulnerability associated with CVE-2023-37299. Users are urged to update their Joplin applications to version 2.11.5 or later to ensure they are protected against this vulnerability.

Conclusion

CVE-2023-37299 poses significant security risks due to the potential execution of arbitrary code via an XSS vulnerability in Joplin versions before 2.11.5. Users are encouraged to update their applications to the latest version, and exercise caution when importing or viewing notes from untrusted or unknown sources. By keeping the Joplin application updated and following safe practices, users can mitigate the risk associated with this vulnerability and ensure the continued privacy and security of their data.

Timeline

Published on: 06/30/2023 15:15:00 UTC
Last modified on: 07/06/2023 18:54:00 UTC