8.7
HIGH CVSS 4.0
CVE-2026-63101
Open Event Server 1.19.1 Unauthenticated Member Roster Export via CSV Export Endpoint
Description

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.

INFO

Published Date :

July 17, 2026, 5:17 p.m.

Last Modified :

July 17, 2026, 7:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-63101 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 HIGH [email protected]
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH [email protected]
Solution
Update Open Event Server to patch the authentication bypass vulnerability.
  • Update Open Event Server to version 1.19.2 or later.
  • Verify group follower export endpoint requires authentication.
  • Implement authentication checks on all endpoints.
  • Remove sensitive data from exported rosters.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-63101.

URL 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
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-63101 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-63101 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-63101 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jul. 17, 2026

    Action Type Old Value New Value
    Added SSVC {'id': 'CVE-2026-63101', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-17T17:24:23.081296Z'}
  • New CVE Received by [email protected]

    Jul. 17, 2026

    Action Type Old Value New Value
    Added Affected [{'repo': 'https://github.com/fossasia/open-event-server', 'vendor': 'fossasia', 'product': 'open-event-server', 'versions': [{'status': 'affected', 'version': '0', 'versionType': 'semver', 'lessThanOrEqual': '1.19.1'}], 'packageURL': 'pkg:github/fossasia/open-event-server', 'defaultStatus': 'affected'}]
    Added Tag unsupported-when-assigned
    Added Description 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.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
    Added CWE CWE-306
    Added Reference https://github.com/geo-chen/oss/blob/main/open-event-server.md
    Added Reference https://www.vulncheck.com/advisories/open-event-server-unauthenticated-member-roster-export-via-csv-export-endpoint
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.