Summary
Canarytokens.org was vulnerable to a blind SSRF in the Webhook alert feature.
Details
When a Canarytoken is created, users choose to receive alerts either via email or via a webhook. If a webhook is supplied when a Canarytoken is first created, the site will make a test request to the supplied URL to ensure it accepts alert notification HTTP requests.
No safety checks were performed on the URL, leading to a Server-Side Request Forgery vulnerability. The SSRF is Blind because the content of the response is not displayed to the creating user; they are simply told whether an error occurred in making the test request.
Scope of impact
Using the Blind SSRF, it was possible to map out open ports for IPs inside the Canarytokens.org infrastructure.
Patches
This issue is now patched on Canarytokens.org.
Users of self-hosted Canarytokens installations can update by pulling the latest Docker image (or any Docker image after sha-097d91a):
$ docker pull thinkst/canarytokens:latest
Acknowledgements
We thank Viktor Chuchurski and Francesco Lacerenza (Doyensec https://doyensec.com/).
Summary
Canarytokens.org was vulnerable to a blind SSRF in the Webhook alert feature.
Details
When a Canarytoken is created, users choose to receive alerts either via email or via a webhook. If a webhook is supplied when a Canarytoken is first created, the site will make a test request to the supplied URL to ensure it accepts alert notification HTTP requests.
No safety checks were performed on the URL, leading to a Server-Side Request Forgery vulnerability. The SSRF is Blind because the content of the response is not displayed to the creating user; they are simply told whether an error occurred in making the test request.
Scope of impact
Using the Blind SSRF, it was possible to map out open ports for IPs inside the Canarytokens.org infrastructure.
Patches
This issue is now patched on Canarytokens.org.
Users of self-hosted Canarytokens installations can update by pulling the latest Docker image (or any Docker image after
sha-097d91a):Acknowledgements
We thank Viktor Chuchurski and Francesco Lacerenza (Doyensec https://doyensec.com/).