CVE-2025-27409: Joplin Server Vulnerable to Path Traversal

Vulnerability summary

CVE-2025-27409 is a high (CVSS 7.5) Path Traversal vulnerability in joplin_project joplin. EPSS estimates a 0.65% chance of exploitation in the next 30 days, higher than 50.4% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 30-04-2025
   PublishedVulnerability first disclosed.
2. 30-04-2025
   Last modifiedVulnerability information updated.

Description

Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks. Prior to version 3.3.3, path traversal is possible in Joplin Server if static file path starts with `css/pluginAssets` or `js/pluginAssets`. The `findLocalFile` function in the `default route` calls `localFileFromUrl` to check for special `pluginAssets` paths. If the function returns a path, the result is returned directly, without checking for path traversal. The vulnerability allows attackers to read files outside the intended directories. This issue has been patched in version 3.3.3.

• CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.