fossasia open-event-server up to 1.19.1 Group Followers CSV Export Endpoint missing authentication

Summaryinfo

A vulnerability marked as problematic has been reported in fossasia open-event-server up to 1.19.1. The impacted element is an unknown function of the component Group Followers CSV Export Endpoint. The manipulation leads to missing authentication. This vulnerability only affects products that are no longer supported by the maintainer. This vulnerability is traded as CVE-2026-63101. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability was found in fossasia open-event-server up to 1.19.1 and classified as problematic. This issue affects an unknown code of the component Group Followers CSV Export Endpoint. The manipulation with an unknown input leads to a missing authentication vulnerability. Using CWE to declare the problem leads to CWE-306. The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources. Impacted is confidentiality. The summary by CVE is:

Open Event Server through 1.19.1 contains a missing authentication vulnerability that allows unauthenticated attackers to export the complete member roster of any group, including email addresses, names, join dates, and roles, by submitting requests to the group followers CSV export endpoint which lacks any authentication decorator. Attackers can enumerate sequential group IDs via brute-force, trigger an export via the unauthenticated POST endpoint, then poll the unauthenticated task status endpoint until completion to retrieve a download URL containing the full member CSV.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-63101 since 07/15/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/17/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Vendor

• fossasia

Name

• open-event-server

Version

• 1.19.0
• 1.19.1

Support

• end of life

CPE 2.3info

• 🔒
• 🔒

CPE 2.2info

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• 🔒

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