CVE-2023-38506: Cross-site Scripting (XSS) when pasting HTML into the rich text editor in Joplin

Vulnerability summary

CVE-2023-38506 is a high (CVSS 8.2) Cross-site Scripting vulnerability in joplin_project joplin. EPSS estimates a 0.42% chance of exploitation in the next 30 days, higher than 35.4% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 21-06-2024
   PublishedVulnerability first disclosed.
2. 02-08-2024
   Last modifiedVulnerability information updated.

Description

Joplin is a free, open source note taking and to-do application. A Cross-site Scripting (XSS) vulnerability allows pasting untrusted data into the rich text editor to execute arbitrary code. HTML pasted into the rich text editor is not sanitized (or not sanitized properly). As such, the `onload` attribute of pasted images can execute arbitrary code. Because the TinyMCE editor frame does not use the `sandbox` attribute, such scripts can access NodeJS's `require` through the `top` variable. From this, an attacker can run arbitrary commands. This issue has been addressed in version 2.12.10 and users are advised to upgrade. There are no known workarounds for this vulnerability.

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.