Mattermost Plugins versions <=11.4 11.0.4 11.1.3 11.3.2 10.11.11.0 fail to validate incoming request size which allows an authenticated attacker to cause service disruption via the webhook endpoint. Mattermost Advisory ID: MMSA-2026-00589
PUBLISHED5.2CWE-400
Improper Input Validation in Zoom Plugin Webhook Handler
Problem type
Affected products
Mattermost
Mattermost
<= 11.0.4 - AFFECTED
<= 11.1.3 - AFFECTED
<= 11.3.2 - AFFECTED
<= 10.11.11 - AFFECTED
11.5.0 - UNAFFECTED
11.4.1 - UNAFFECTED
11.3.2 - UNAFFECTED
11.2.4 - UNAFFECTED
10.11.12 - UNAFFECTED
References
GitHub Security Advisories
GHSA-f499-j7p4-wm44
Mattermost Plugins versions <=11.4 11.0.4 11.1.3 11.3.2 10.11.11.0 fail to validate incoming...
https://github.com/advisories/GHSA-f499-j7p4-wm44Mattermost Plugins versions <=11.4 11.0.4 11.1.3 11.3.2 10.11.11.0 fail to validate incoming request size which allows an authenticated attacker to cause service disruption via the webhook endpoint. Mattermost Advisory ID: MMSA-2026-00589
JSON source
https://cveawg.mitre.org/api/cve/CVE-2026-3116Click to expand
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"cveId": "CVE-2026-3116",
"assignerOrgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee",
"assignerShortName": "Mattermost",
"dateUpdated": "2026-03-26T17:51:14.971Z",
"dateReserved": "2026-02-24T11:10:17.757Z",
"datePublished": "2026-03-26T16:19:32.607Z",
"state": "PUBLISHED"
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"containers": {
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"title": "Improper Input Validation in Zoom Plugin Webhook Handler",
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"value": "Mattermost Plugins versions <=11.4 11.0.4 11.1.3 11.3.2 10.11.11.0 fail to validate incoming request size which allows an authenticated attacker to cause service disruption via the webhook endpoint. Mattermost Advisory ID: MMSA-2026-00589"
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"problemTypes": [
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"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "HIGH",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "HIGH",
"baseScore": 4.9,
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}
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"solutions": [
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"value": "Update Mattermost Plugins to versions 11.5.0, 11.4.1, 11.3.2, 11.2.4, 10.11.12 or higher."
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"credits": [
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"adp": [
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