CVE-2026-107396 Indico: Cross-Site-Scripting in link fields
Attackers can inject malicious JavaScript via crafted URLs in event fields, allowing script execution in victims' browsers within the Indico origin.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-107396?
CVE-2026-107396 is a medium-severity cross-site scripting vulnerability in indico, published on 8 Oct 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
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 manage events or create content, including speakers who can upload material, can store crafted javascript URLs in fields that accept custom URLs. A user who follows one of these URLs can execute attacker-controlled script in the user's browser in the Indico origin. This issue is fixed in version 3.3.13.
Weakness: CWE-692
Which versions are affected by CVE-2026-107396?
3 open source packages ship an affected version, including indico.
| Package | Affected | Fixed in |
|---|---|---|
indico PyPI | All versions | 3.3.13 |
indico PyPI | All versions | 3.3.13 |
indico PyPI | All versions | 3.3.13 |
How do I fix CVE-2026-107396?
Upgrade indico to 3.3.13 or later.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-107396 being exploited?
There is no known exploitation of CVE-2026-107396 in the wild and no public exploit code.
Sources
Also known as GHSA-c4wc-ggrj-jg9v, PYSEC-2026-4227.