CVEvulnerability
CVE-2026-18223
5.0 MEDIUM
Official page ↗
- Status
- Analyzed
- Published
- 2026-10-16
- Last modified
- 2026-10-29
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 5.0 MEDIUM — CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:L/A:N
- Weaknesses
- CWE-863
Description
Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to validate the invited recipient's email address when redeeming team and guest invitation tokens, which allows an authenticated attacker to join a team or gain unauthorized access to private channels via a forwarded or leaked invitation link.. Mattermost Advisory ID: MMSA-2026-00747
Affected configurations
• mattermost mattermost server (>= 11.7.0 < 11.7.10)
• mattermost mattermost server (>= 11.8.0 < 11.8.6)
• mattermost mattermost server (>= 11.9.0 < 11.9.2)
• mattermost mattermost server 11.10.0
Related
Weakness · CWE (1)
- CWE-863 Incorrect Authorization weakness
References
- https://mattermost.com/security-updates Vendor Advisory