CVE-2026-107397: Indico: Cross-Site-Scripting in minutes editor
Impact There is a Cross-Site-Scripting vulnerability in the minute editor conflict UI tha's shown when concurrent edits are made to the same minutes in an event.
Patches You should to update to Indico 3.3.13 as soon as possible. See the docs for instructions on how to update.
Workarounds - Set CSPENABLED = True in indico.conf - this is recommended regardless of updating. - Only let trustworthy users create content (including minutes which speakers can typically do as well) on Indico.
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, users who can create content, including speakers who can create minutes, can store crafted HTML in event minutes. When concurrent edits are made to the same minutes, the minute editor conflict UI can execute attacker-controlled script in the viewer's browser in the Indico origin. 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 - Configuration
Set CSP_ENABLED = True in indico.conf; this is recommended regardless of updating.
Indico CSP_ENABLED = True - Compensating control
Only allow trustworthy users to create content in Indico, including minutes that speakers can create.
Event History
Frequently Asked Questions
Who can exploit this issue, and who is exposed to the resulting script execution?
An attacker needs an account with permission to create content, such as a speaker who can create minutes. The script executes in the browser of a user viewing the minutes editor conflict interface.
What conditions are required to trigger the vulnerable interface?
The attacker must store crafted HTML in event minutes, and concurrent edits to the same minutes must occur. The issue is triggered when the conflict UI handles those simultaneous edits.
Which versions are affected, and what is the remediation?
Indico versions prior to 3.3.13 are affected. Upgrade to version 3.3.13 to obtain the fix.