CVE-2026-63101
highpriority · track · 0OT risk · elevatedEPSS 0.005 · 44 %ileEUEPSS · scored 2026-10-28
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
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.6–8.7
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (1)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6)
External citations — patches, advisories, analysis.
- https://github.com/geo-chen/oss/blob/main/open-event-server.mdcnnvd
- https://www.vulncheck.com/advisories/open-event-server-unauthenticated-member-roster-export-via-csv-export-endpointcnnvd
- https://github.com/geo-chen/oss/blob/main/open-event-server.mdenisa_euvd
- https://www.vulncheck.com/advisories/open-event-server-unauthenticated-member-roster-export-via-csv-export-endpointenisa_euvd
- https://github.com/geo-chen/oss/blob/main/open-event-server.mdnvd
- https://www.vulncheck.com/advisories/open-event-server-unauthenticated-member-roster-export-via-csv-export-endpointnvd
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