Unbounded Request Body Read in MS Teams Plugin {{/lifecycle}} Webhook Endpoint_CVE-2026-21388

{
    "lastseen": "",
    "description": "Mattermost Plugins versions <=2.3.1 fail to limit the request body size on the {{/lifecycle}} webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00610",
    "published": "2026-04-09T10:09:23.899Z",
    "modified": "2026-04-09T11:44:54.614Z",
    "type": "cve",
    "title": "Unbounded Request Body Read in MS Teams Plugin {{/lifecycle}} Webhook Endpoint",
    "source": "Mattermost",
    "references": "https://mattermost.com/security-updates",
    "id": "CVE-2026-21388",
    "bulletinFamily": "",
    "cwe": [
        "CWE-770"
    ],
    "cvelist": null,
    "sourceData": "Mattermost Mattermost 0",
    "sourceHref": "",
    "cvss": {
        "score": 3.7,
        "severity": "LOW",
        "vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L",
        "version": "3.1"
    },
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        "baseScore": 0,
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        "privilegesRequired": "",
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        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
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    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "Mattermost",
    "version": "0",
    "vendor": "Mattermost",
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}