CVE-2025-53640 Indico vulnerable to user enumeration via API endpoint
Attackers can enumerate user details like names and emails via an API endpoint, exposing sensitive information in Indico event management systems.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-53640?
CVE-2025-53640 is a medium-severity vulnerability in indico, published on 14 Jul 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Indico is an event management system that uses Flask-Multipass, a multi-backend authentication system for Flask. Starting in version 2.2 and prior to version 3.3.7, an endpoint used to display details of users listed in certain fields (such as ACLs) could be misused to dump basic user details (such as name, affiliation and email) in bulk. Version 3.3.7 fixes the issue. Owners of instances that allow everyone to create a user account, who wish to truly restrict access to these user details, should consider restricting user search to managers. As a workaround, it is possible to restrict access to the affected endpoints (e.g. in the webserver config), but doing so would break certain form fields which could no longer show the details of the users listed in those fields, so upgrading instead is highly recommended.
Which versions are affected by CVE-2025-53640?
3 open source packages ship an affected version, including indico. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
indico PyPI | From 2.2 | 3.3.7 |
indico PyPI | From 2.2 | 3.3.7 |
indico PyPI | From 2.2 | 3.3.7 |
Products include Cern Indico.
How do I fix CVE-2025-53640?
Upgrade indico to 3.3.7 or later.
Is CVE-2025-53640 being exploited?
There is no known exploitation of CVE-2025-53640 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in indico
- CVE-2026-33046 Indico discloses local files resulting in Remote Code Execution through LaTeX injection
- CVE-2021-30185 Indico Tampering with links (e.g. password reset) in sent emails
- CVE-2026-25738 Indico has Server-Side Request Forgery (SSRF) in multiple places
- CVE-2026-28352 Indico missing access check in event series management API
- CVE-2026-25739 Indico affected by Cross-Site-Scripting via material uploads
Sources
Also known as GHSA-q28v-664f-q6wj, PYSEC-2026-1462.