CVE-2026-9693 (GCVE-0-2026-9693)

Vulnerability from cvelistv5 – Published: 2026-08-17 22:07 – Updated: 2026-08-17 22:07
VLAI
Title
Mattermost thread memberships persist after team removal, exposing private channel thread metadata on re-invite
Summary
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
Severity
3.5 (Low)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N
CWE
Assigner
References
URL Tags
https://mattermost.com/security-updates vendor-advisory
Impacted products
Vendor Product Version CPE status
Mattermost Mattermost Affected: 10.11.0 , ≤ 10.11.20 (semver)
Affected: 11.7.0 , ≤ 11.7.5 (semver)
Unaffected: 11.9.0
Unaffected: 10.11.21
Unaffected: 11.7.6
guessed Create a notification for this product.
Credits
kiwi_71
Show details on NVD website
To clipboard 

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            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
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          "value": "Update Mattermost to versions 11.9.0, 10.11.21, 11.7.6 or higher."
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      "source": {
        "advisory": "MMSA-2026-00682",
        "defect": [
          "https://mattermost.atlassian.net/browse/MM-69006"
        ],
        "discovery": "EXTERNAL"
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    "dateReserved": "2026-05-27T10:58:39.051Z",
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  }
}



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