CVE-2026-25527: changedetection.io vulnerable to unauthenticated static path traversal

Vulnerability summary

CVE-2026-25527 is a medium (CVSS 5.3) Path Traversal vulnerability in dgtlmoon changedetection.io. EPSS estimates a 1.00% chance of exploitation in the next 30 days, higher than 62.4% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 19-02-2026
   PublishedVulnerability first disclosed.
2. 19-02-2026
   Last modifiedVulnerability information updated.

Description

changedetection.io is a free open source web page change detection tool. In versions prior to 0.53.2, the `/static/<group>/<filename>` route accepts `group=".."`, which causes `send_from_directory("static/..", filename)` to execute. This moves the base directory up to `/app/changedetectionio`, enabling unauthenticated local file read of application source files (e.g., `flask_app.py`). Version 0.53.2 fixes the issue.

• 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.