{"id":"CVE-2025-9076","state":"PUBLISHED","title":"Mattermost Server exposes sensitive user credentials during shared channel membership synchronization","description":"Mattermost versions 10.10.x <= 10.10.1 fail to properly sanitize user data during shared channel membership synchronization, which allows malicious or compromised remote clusters to access sensitive user information via unsanitized user objects. This vulnerability affects Mattermost Server instances with shared channels enabled.","publishedAt":"2025-09-15T10:06:15.094Z","updatedAt":"2025-09-15T14:05:16.235Z","severity":{"score":6.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N","source":"Mattermost"},"assigner":"Mattermost","products":["Mattermost Mattermost"],"affected":[{"vendor":"Mattermost","product":"Mattermost","defaultStatus":"unaffected","versions":[{"version":"10.10.0","status":"affected","lessThanOrEqual":"10.10.1","versionType":"semver"},{"version":"10.11.0","status":"unaffected"},{"version":"10.10.2","status":"unaffected"}]}],"references":["https://mattermost.com/security-updates"],"weaknesses":["CWE-862"],"ingestedAt":"2026-10-29T20:10:13.529Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/9xxx/CVE-2025-9076.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2025-9076","state":"PUBLISHED","datePublished":"2025-09-15T10:06:15.094Z","dateUpdated":"2025-09-15T14:05:16.235Z","assignerShortName":"Mattermost","assignerOrgId":"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee","dateReserved":"2025-08-15T15:26:17.148Z"},"containers":{"cna":{"title":"Mattermost Server exposes sensitive user credentials during shared channel membership synchronization","descriptions":[{"lang":"en","value":"Mattermost versions 10.10.x <= 10.10.1 fail to properly sanitize user data during shared channel membership synchronization, which allows malicious or compromised remote clusters to access sensitive user information via unsanitized user objects. This vulnerability affects Mattermost Server instances with shared channels enabled."}],"affected":[{"vendor":"Mattermost","product":"Mattermost","defaultStatus":"unaffected","versions":[{"version":"10.10.0","status":"affected","lessThanOrEqual":"10.10.1","versionType":"semver"},{"version":"10.11.0","status":"unaffected"},{"version":"10.10.2","status":"unaffected"}]}],"references":[{"url":"https://mattermost.com/security-updates"}],"metrics":[{"cvssV3_1":{"attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"HIGH","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"NONE","version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N","baseSeverity":"MEDIUM","baseScore":6.5},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-862","lang":"en","type":"CWE","description":"CWE-862: Missing Authorization"}]}],"providerMetadata":{"shortName":"Mattermost","orgId":"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee","dateUpdated":"2025-09-15T10:06:15.094Z"},"credits":[{"lang":"en","type":"finder","value":"daw10"}],"solutions":[{"value":"Update Mattermost to versions 10.11.0, 10.10.2 or higher.","lang":"en"}],"source":{"advisory":"MMSA-2025-00513","defect":["https://mattermost.atlassian.net/browse/MM-64926"],"discovery":"EXTERNAL"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2025-09-15T14:05:07.348669Z","id":"CVE-2025-9076","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-09-15T14:05:16.235Z"}}]}}}