# CVE-2026-9693

## Summary

- **CVE ID:** CVE-2026-9693
- **Severity:** LOW
- **CVSS Score:** 3.5 (CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N)
- **CWE:** CWE-459
- **Published:** Aug 17, 2026
- **Last Modified:** Aug 18, 2026

## Description

Mattermost versions 10.11.x <= 10.11.20, 11.7.x <= 11.7.5 Mattermost fails to remove thread membership records when a user is removed from or leaves a team, which allows a previously removed user who is later re-invited to the team to view private channel thread root post content and metadata via the team threads API.. Mattermost Advisory ID: MMSA-2026-00682

## Affected Products

- Mattermost — Mattermost (10.11.0)
- Mattermost — Mattermost (11.7.0)
- Mattermost — Mattermost (11.9.0)
- Mattermost — Mattermost (10.11.21)
- Mattermost — Mattermost (11.7.6)

## References

- [CNA](https://mattermost.com/security-updates)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.16%
- **EPSS Percentile:** 5.4

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-10._