GHSA-4r7v-whpg-8rx3
CRITICALGHSA-4r7v-whpg-8rx3 is a critical-severity (CVSS 10) CWE-1336 vulnerability in changedetection-io. 1 public exploit reference exists, so weaponization risk is real. O3 Security confirms whether GHSA-4r7v-whpg-8rx3 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
changedetection.io has a Server Side Template Injection using Jinja2 which allows Remote Command Execution
Blast Radius
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Description
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.
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
- Create/Edit a URL watch item
- Under Notifications tab insert this payload:
{{ self.__init__.__globals__.__builtins__.__import__('os').popen('id').read() }}
- See Telegram (or other supported messaging app) notification
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
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | changedetection-io | all versions | 0.45.21 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for changedetection-io. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update changedetection-io to 0.45.21 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4r7v-whpg-8rx3 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-4r7v-whpg-8rx3 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-4r7v-whpg-8rx3. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-4r7v-whpg-8rx3 in your dependencies?
O3 detects GHSA-4r7v-whpg-8rx3 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.