{"id":"CVE-2026-8823","state":"PUBLISHED","title":"User Manager can demote bot accounts to guest without bot-management permission","description":"Mattermost versions 11.7.x <= 11.7.0, 10.11.x <= 10.11.17 fail to validate bot targets when demoting users to guests which allows a lower-privileged administrator to degrade arbitrary bot accounts via the standard demote-user API.. Mattermost Advisory ID: MMSA-2026-00669","publishedAt":"2026-06-22T13:41:28.404Z","updatedAt":"2026-06-22T16:12:31.350Z","severity":{"score":3.8,"label":"Low","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:L","source":"Mattermost"},"assigner":"Mattermost","products":["Mattermost Mattermost"],"affected":[{"vendor":"Mattermost","product":"Mattermost","defaultStatus":"unaffected","versions":[{"version":"11.7.0","status":"affected","lessThanOrEqual":"11.7.0","versionType":"semver"},{"version":"10.11.0","status":"affected","lessThanOrEqual":"10.11.17","versionType":"semver"},{"version":"11.8.0","status":"unaffected"},{"version":"11.7.1","status":"unaffected"},{"version":"10.11.18","status":"unaffected"}]}],"references":["https://mattermost.com/security-updates"],"weaknesses":["CWE-863"],"ingestedAt":"2026-10-29T20:13:26.108Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/8xxx/CVE-2026-8823.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-8823","state":"PUBLISHED","datePublished":"2026-06-22T13:41:28.404Z","dateUpdated":"2026-06-22T16:12:31.350Z","assignerShortName":"Mattermost","assignerOrgId":"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee","dateReserved":"2026-05-18T10:05:31.691Z"},"containers":{"cna":{"title":"User Manager can demote bot accounts to guest without bot-management permission","descriptions":[{"lang":"en","value":"Mattermost versions 11.7.x <= 11.7.0, 10.11.x <= 10.11.17 fail to validate bot targets when demoting users to guests which allows a lower-privileged administrator to degrade arbitrary bot accounts via the standard demote-user API.. Mattermost Advisory ID: MMSA-2026-00669"}],"affected":[{"vendor":"Mattermost","product":"Mattermost","defaultStatus":"unaffected","versions":[{"version":"11.7.0","status":"affected","lessThanOrEqual":"11.7.0","versionType":"semver"},{"version":"10.11.0","status":"affected","lessThanOrEqual":"10.11.17","versionType":"semver"},{"version":"11.8.0","status":"unaffected"},{"version":"11.7.1","status":"unaffected"},{"version":"10.11.18","status":"unaffected"}]}],"references":[{"url":"https://mattermost.com/security-updates","name":"MMSA-2026-00669","tags":["vendor-advisory"]}],"metrics":[{"cvssV3_1":{"attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"HIGH","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"LOW","availabilityImpact":"LOW","version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:L","baseSeverity":"LOW","baseScore":3.8},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-863","lang":"en","type":"CWE","description":"CWE-863: Incorrect Authorization"}]}],"providerMetadata":{"shortName":"Mattermost","orgId":"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee","dateUpdated":"2026-06-22T13:41:28.404Z"},"credits":[{"lang":"en","type":"finder","value":"Edgar Bellot Micó"}],"solutions":[{"value":"Update Mattermost to versions 11.8.0, 11.7.1, 10.11.18 or higher.","lang":"en"}],"source":{"advisory":"MMSA-2026-00669","defect":["https://mattermost.atlassian.net/browse/MM-68700"],"discovery":"{\"self\"=>\"https://mattermost.atlassian.net/rest/api/2/customFieldOption/10557\", \"value\"=>\"Internal\", \"id\"=>\"10557\"}"},"x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-22T16:12:21.701325Z","id":"CVE-2026-8823","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-06-22T16:12:31.350Z"}}]}}}