All vulnerabilities
CVE-2024-32651GHSA-4r7v-whpg-8rx3PYSEC-2026-310

changedetection.io has a Server Side Template Injection using Jinja2 which allows Remote Command Execution

dgtlmoon changedetection.iopipLibraries & packages
Open in ThreatlineRecord JSON
CVSS
10.0Critical
ExploitationPublic exploit codeCISA's assessment says proof of concept code is public, assessed 7 Jun 2024. Not in the KEV catalogCISA via CVE List
Exploit odds (EPSS)83.6%Chance of exploitation activity in the next 30 days, higher than 99% of CVEs. Scored 27 Oct 2026FIRST EPSS
Fixed in0.45.21Fixed versionGitHub
Published25 Apr 2024Updated 27 Oct 2026CVE List

What fixes it

  • 0.45.21changedetection.io, pipGitHub
  • 0.45.21changedetection-io, PyPIOSVpip install "changedetection-io>=0.45.21"

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Public exploit code and templates 1

  • Scanner templateChange Detection - Server Side Template InjectionNuclei

Listed so defenders can prioritize. Threatline links to the source and does not host exploit code.

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

  1. Create/Edit a URL watch item
  2. Under *Notifications* tab insert this payload: 
{{ self.__init__.__globals__.__builtins__.__import__('os').popen('id').read() }}

!Screenshot from 2024-04-19 15-46-04

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

!Screenshot from 2024-04-19 16-02-12

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

Text from GitHub Advisory Database

Affected versions 53

  • changedetection.io, pip<= 0.45.20GitHub
  • changedetection.ioaffected: <= 0.45.20CVE List
  • changedetection-io, PyPIfrom first release, fixed in 0.45.21OSV
  • changedetection-io, PyPI0.38.2OSV
  • changedetection-io, PyPI0.39OSV
  • changedetection-io, PyPI0.39.1OSV
  • changedetection-io, PyPI0.39.10OSV
  • changedetection-io, PyPI0.39.10.post1OSV
  • changedetection-io, PyPI0.39.10.post2OSV
  • changedetection-io, PyPI0.39.11OSV
  • changedetection-io, PyPI0.39.12OSV
  • changedetection-io, PyPI0.39.13OSV
  • changedetection-io, PyPI0.39.13.1OSV
  • changedetection-io, PyPI0.39.14OSV
  • changedetection-io, PyPI0.39.14.1OSV
  • changedetection-io, PyPI0.39.15OSV
  • changedetection-io, PyPI0.39.16OSV
  • changedetection-io, PyPI0.39.17OSV
  • changedetection-io, PyPI0.39.17.1OSV
  • changedetection-io, PyPI0.39.17.2OSV
  • changedetection-io, PyPI0.39.18OSV
  • changedetection-io, PyPI0.39.19OSV
  • changedetection-io, PyPI0.39.19.1OSV
  • changedetection-io, PyPI0.39.2OSV
  • changedetection-io, PyPI0.39.20OSV
  • changedetection-io, PyPI0.39.20.1OSV
  • changedetection-io, PyPI0.39.20.2OSV
  • changedetection-io, PyPI0.39.20.3OSV
  • changedetection-io, PyPI0.39.20.4OSV
  • changedetection-io, PyPI0.39.21OSV
  • changedetection-io, PyPI0.39.21.1OSV
  • changedetection-io, PyPI0.39.22OSV
  • changedetection-io, PyPI0.39.22.1OSV
  • changedetection-io, PyPI0.39.3OSV
  • changedetection-io, PyPI0.39.4OSV
  • changedetection-io, PyPI0.39.5OSV
  • changedetection-io, PyPI0.39.6OSV
  • changedetection-io, PyPI0.39.7OSV
  • changedetection-io, PyPI0.39.8OSV
  • changedetection-io, PyPI0.39.9OSV
  • changedetection-io, PyPI0.40.0OSV
  • changedetection-io, PyPI0.40.0.1OSV
  • changedetection-io, PyPI0.40.0.2OSV
  • changedetection-io, PyPI0.40.0.3OSV
  • changedetection-io, PyPI0.40.0.4OSV
  • changedetection-io, PyPI0.40.1.0OSV
  • changedetection-io, PyPI0.40.1.1OSV
  • changedetection-io, PyPI0.40.2OSV
  • changedetection-io, PyPI0.40.3OSV
  • changedetection-io, PyPI0.41OSV
  • changedetection-io, PyPI0.41.1OSV
  • changedetection-io, PyPI0.42OSV
  • changedetection-io, PyPI0.42.1OSV

References 9