# CVE-2026-9820: Mattermost schemes teams endpoint exposes private team invite IDs

> CVE-2026-9820: Mattermost schemes teams endpoint exposes private team invite IDs. CVSS 3.8 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-9820
Last updated: 2026-07-13T20:38:36Z

- Published: 2026-07-13 10:51 UTC · Updated: 2026-07-13 20:38 UTC · Assigner: Mattermost
- CVSS: 3.8 (CVSS 3.1) · Severity: Low · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N
- EPSS: 0.26%, 17th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-862

## Description

Mattermost versions 11.7.x \<= 11.7.2, 10.11.x \<= 10.11.19 fail to sanitize team objects returned by the scheme teams endpoint, which allows a user with the User Manager role to obtain invite links for private teams and use them to join or share access to those teams via the scheme teams API endpoint.. Mattermost Advisory ID: MMSA-2026-00671

## Affected vendors and products

- Mattermost: Mattermost

## Tracked companies

- [Mattermost](https://rewindex.com/company/mattermost.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-9820)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-9820)
- [https://mattermost.com/security-updates](https://mattermost.com/security-updates)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-9820 · Markdown: https://rewindex.com/cve/CVE-2026-9820.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-9820 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:50:30.676Z