CVE-2026-63101

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/geo-chen/oss/blob/main/open-event-server.md
https://www.vulncheck.com/advisories/open-event-server-unauthenticated-member-roster-export-via-csv-export-endpoint

Configurations

No configuration.

History

17 Jul 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-17 17:17

Updated : 2026-07-17 19:17

NVD link : CVE-2026-63101

Mitre link : CVE-2026-63101

CVE.ORG link : CVE-2026-63101

JSON object : View

Products Affected

No product.

CWE

CWE-306

Missing Authentication for Critical Function

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