{"id":"CVE-2026-6689","sourceIdentifier":"responsibledisclosure@mattermost.com","published":"2026-06-12T17:16:27.180","lastModified":"2026-06-18T14:34:19.950","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 Fail to enforce PermissionInviteUser when setting AllowOpenInvite or AllowedDomains during team creation (the check was only applied on update/patch), which allows an authenticated user holding PermissionCreateTeam but not PermissionInviteUser on the resulting team to configure invite-controlled team settings (make the team publicly joinable via open invite and/or constrain membership via allowed domains) that they are not permitted to set on an existing team via POST /api/v4/teams with allow_open_invite: true and/or a non-empty allowed_domains in the request body.. Mattermost Advisory ID: MMSA-2026-00655"}],"affected":[{"source":"responsibledisclosure@mattermost.com","affectedData":[{"vendor":"Mattermost","product":"Mattermost","defaultStatus":"unaffected","versions":[{"version":"11.6.0","lessThanOrEqual":"11.6.1","versionType":"semver","status":"affected"},{"version":"11.5.0","lessThanOrEqual":"11.5.4","versionType":"semver","status":"affected"},{"version":"10.11.0","lessThanOrEqual":"10.11.15","versionType":"semver","status":"affected"},{"version":"10.11.0","lessThanOrEqual":"10.11.16","versionType":"semver","status":"affected"},{"version":"11.7.0","status":"unaffected"},{"version":"11.6.2","status":"unaffected"},{"version":"11.5.5","status":"unaffected"},{"version":"10.11.16","status":"unaffected"},{"version":"10.11.17","status":"unaffected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"responsibledisclosure@mattermost.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N","baseScore":4.3,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"LOW","availabilityImpact":"NONE"},"exploitabilityScore":2.8,"impactScore":1.4}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-06-12T17:18:46.355666Z","id":"CVE-2026-6689","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"responsibledisclosure@mattermost.com","type":"Secondary","description":[{"lang":"en","value":"CWE-862"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*","versionStartIncluding":"10.11.0","versionEndExcluding":"10.11.17","matchCriteriaId":"F9018E52-5C7F-4E59-B637-604B8EECD974"},{"vulnerable":true,"criteria":"cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*","versionStartIncluding":"11.5.0","versionEndExcluding":"11.5.5","matchCriteriaId":"DF287562-A912-43DD-8FAC-0CD8EC7BEF7E"},{"vulnerable":true,"criteria":"cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*","versionStartIncluding":"11.6.0","versionEndExcluding":"11.6.2","matchCriteriaId":"AFCFC389-02A5-45CD-8EEB-9ED208C0EE83"}]}]}],"references":[{"url":"https://mattermost.com/security-updates","source":"responsibledisclosure@mattermost.com","tags":["Vendor Advisory"]}]}