CVE-2026-107394: Indico: Incomplete Server-Side Request Forgery (SSRF) check
Impact Indico makes outgoing requests to user-provides URLs in various places. This is mostly intentional and part of Indico's functionality, but of course it is never intended to let you access "special" targets such as localhost or cloud metadata endpoints. The previous fix (CVE-2026-25738) did not cover an edge case so it was still possible to craft a URL that pointed to a local target but was accepted as valid by Indico.
Patches You should to update to Indico 3.3.13 as soon as possible. See the docs for instructions on how to update.
Workarounds If you do not have IPs that expose sensitive data without authentication (typically because you do not host Indico on AWS), this vulnerability doesn't impact you and you can ignore it (but please upgrade anyway). Also, only event organizers can access endpoints where SSRF could be used to actually see the data returned by such a request. So if you trust your event organizers, the risk is also very limited.
For additional security, both before and after patching, you could also use the common proxy-related environment variables (in particular httpproxy and httpsproxy) to force outgoing requests to go through a proxy that limits requests in whatever way you deem useful/necessary. These environment variables would need to be set both on the indico-uwsgi and indico-celery services. Please note that setting up such a proxy is not something we can help you with.
For more information If you have any questions or comments about this advisory:
- Open a thread in our forum - Email us privately at indico-team@cern.ch
Other sources
Indico is an event management system that uses Flask-Multipass, a multi-backend authentication system for Flask. Prior to 3.3.13, the previous fix for CVE-2026-25738 did not cover an edge case, allowing an event organizer to submit a crafted URL that points to a prohibited local target but is accepted as valid by Indico. The organizer can read data returned by the target through affected Indico features. This issue is fixed in version 3.3.13.
— MITRE
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
pip/indicoto a version that resolves this vulnerability.Fixed in 3.3.13 - Upgrade
Upgrade
Indicoto a version that resolves this vulnerability.Fixed in 3.3.13 - Compensating control
Set the http_proxy and https_proxy environment variables on both the indico-uwsgi and indico-celery services to force outgoing requests through a proxy that limits requests.
Event History
Frequently Asked Questions
Who can exploit this issue?
An event organizer can exploit it by submitting a crafted URL. The issue requires high privileges, consistent with the listed PR:H attack vector.
What can an attacker access through the vulnerability?
A successful attacker can cause affected Indico features to request a prohibited local target and read data returned by that target. The vulnerability affects confidentiality; no integrity or availability impact is stated.
Which versions are affected and what version fixes it?
Indico versions prior to 3.3.13 are affected. Upgrade to version 3.3.13, which fixes the uncovered edge case in the prior SSRF protection.