CVE intelligence and bounded remediation
CVE-2026-25527 — changedetection.io is a free open source web page change detection tool
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.
- Severity
- Medium
- CVSS
- 5.3 (3.1)
- Published
- 2026-02-19
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-22
Affected products
- webtechnologies / changedetection
Matched remediation archetype
Path traversal, unsafe upload, and file handling
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Trace untrusted filenames, archive entries, URLs, and path segments into read, write, include, extraction, and upload operations.
- Identify filesystem roots, mount permissions, symbolic-link behavior, archive handling, and whether uploaded content is web-accessible or executable.
- Review canonicalization and containment checks across supported operating systems and storage backends.
Remediate safely
- Generate server-side storage identifiers and resolve paths beneath a fixed root using filesystem-aware containment checks.
- Reject absolute, parent-relative, alternate-separator, device, link, and archive entries that escape the intended root.
- Store uploads outside executable or served paths, validate type and size, and use private atomic temporary files.
Authoritative sources
Complete CVE record and remediation plan
The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.