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

> Unauthenticated attackers can read local application source files via path traversal in the static route, exposing sensitive code.

- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Feb 2026
- **Updated:** 19 Feb 2026
- **Also known as:** GHSA-9jj8-v89v-xjvw, PYSEC-2026-2124

## What is CVE-2026-25527?

CVE-2026-25527 is a medium-severity path traversal vulnerability in dgtlmoon changedetection.io, published on 19 Feb 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official 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.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2026-25527?

3 open source packages ship an affected version, including changedetection.io and changedetection-io. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `changedetection.io` | PyPI | All versions | 0.53.2 |
| `changedetection-io` | PyPI | All versions | 0.53.2 |
| `changedetection-io` | PyPI | All versions | 0.53.2 |

Products: Webtechnologies Changedetection.

## How do I fix CVE-2026-25527?

Upgrade changedetection.io to 0.53.2 or later.

## Is CVE-2026-25527 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-25527 exists.

Public exploit code:

- changedetection.io <= 0.52.9 - Unauthenticated Path Traversal (nuclei): http/cves/2026/CVE-2026-25527.yaml

## Other vulnerabilities in dgtlmoon changedetection.io

- [CVE-2026-35490](https://insights.sbomify.com/CVE-2026-35490/): changedetection.io has an Authentication Bypass via Decorator Ordering (critical 9.8)
- [CVE-2026-29039](https://insights.sbomify.com/CVE-2026-29039/): changedetection.io: XPath - Arbitrary File Read via unparsed-text() (high 8.8)
- [CVE-2026-29065](https://insights.sbomify.com/CVE-2026-29065/): changedetection.io: Zip Slip vulnerability in the backup restore functionality (high 8.8)
- [CVE-2026-27696](https://insights.sbomify.com/CVE-2026-27696/): changedetection.io Vulnerable to Server-Side Request Forgery (SSRF) via Watch URLs (high 8.6)
- [CVE-2026-33981](https://insights.sbomify.com/CVE-2026-33981/): Changedetection.io Discloses Environment Variables via jq env Builtin in Include Filters (high 8.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-25527 and fix it if it is affected.

What it is: CVE-2026-25527 is a medium-severity path traversal vulnerability in dgtlmoon changedetection.io, published on 19 Feb 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-25527 exists.

Affected packages and fixed versions:
- changedetection.io (PyPI): affected all versions; fixed in 0.53.2
- changedetection-io (PyPI): affected all versions; fixed in 0.53.2
- changedetection-io (PyPI): affected all versions; fixed in 0.53.2

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-25527/ (Markdown: https://insights.sbomify.com/CVE-2026-25527/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-25527
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-25527
- OSV: https://osv.dev/vulnerability/CVE-2026-25527

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-25527/
Summaries are generated and may contain mistakes; the official description above is the record.