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{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Mattermost", "vendor": "Mattermost", "versions": [{"lessThanOrEqual": "11.8.2", "status": "affected", "version": "11.8.0", "versionType": "semver"}, {"lessThanOrEqual": "11.7.6", "status": "affected", "version": "11.7.0", "versionType": "semver"}, {"lessThanOrEqual": "10.11.21", "status": "affected", "version": "10.11.0", "versionType": "semver"}, {"status": "unaffected", "version": "11.9.0"}, {"status": "unaffected", "version": "11.8.3"}, {"status": "unaffected", "version": "11.7.7"}, {"status": "unaffected", "version": "10.11.22"}]}], "source": "responsibledisclosure@mattermost.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Mattermost versions 11.8.x <= 11.8.2, 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to restrict channel member role assignment to channel-scoped roles which allows a channel administrator to gain additional channel permissions via the channel member roles API.. Mattermost Advisory ID: MMSA-2026-00697"}], "id": "CVE-2026-16048", "lastModified": "2026-08-17T15:16:54.310", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 6.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 3.4, "source": "responsibledisclosure@mattermost.com", "type": "Secondary"}]}, "published": "2026-08-17T15:16:54.310", "references": [{"source": "responsibledisclosure@mattermost.com", "url": "https://mattermost.com/security-updates"}], "sourceIdentifier": "responsibledisclosure@mattermost.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-863"}], "source": "responsibledisclosure@mattermost.com", "type": "Secondary"}]}

{}

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