{"id":"CVE-2025-12421","sourceIdentifier":"responsibledisclosure@mattermost.com","published":"2025-11-27T18:15:46.223","lastModified":"2026-10-19T13:10:00.110","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"Mattermost versions 11.0.x <= 11.0.2, 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to to verify that the token used during the code exchange originates from the same authentication flow, which allows an authenticated user to perform account takeover via a specially crafted email address used when switching authentication methods and sending a request to the /users/login/sso/code-exchange endpoint. The vulnerability requires ExperimentalEnableAuthenticationTransfer to be enabled (default: enabled) and RequireEmailVerification to be disabled (default: disabled)."},{"lang":"es","value":"Las versiones de Mattermost 11.0.x menor o igual que 11.0.2, 10.12.x menor o igual que 10.12.1, 10.11.x menor o igual que 10.11.4, 10.5.x menor o igual que 10.5.12 no verifican que el token utilizado durante el intercambio de código se origine del mismo flujo de autenticación, lo que permite a un usuario autenticado realizar una toma de control de cuenta a través de una dirección de correo electrónico especialmente diseñada, utilizada al cambiar métodos de autenticación y enviar una solicitud al endpoint /users/login/sso/code-exchange. La vulnerabilidad requiere que ExperimentalEnableAuthenticationTransfer esté habilitado (predeterminado: habilitado) y que RequireEmailVerification esté deshabilitado (predeterminado: deshabilitado)."}],"affected":[{"source":"responsibledisclosure@mattermost.com","affectedData":[{"vendor":"Mattermost","product":"Mattermost","defaultStatus":"unaffected","versions":[{"version":"11.0.0","lessThanOrEqual":"11.0.2","versionType":"semver","status":"affected"},{"version":"10.12.0","lessThanOrEqual":"10.12.1","versionType":"semver","status":"affected"},{"version":"10.11.0","lessThanOrEqual":"10.11.4","versionType":"semver","status":"affected"},{"version":"10.5.0","lessThanOrEqual":"10.5.12","versionType":"semver","status":"affected"},{"version":"11.1.0","status":"unaffected"},{"version":"11.0.3","status":"unaffected"},{"version":"10.12.2","status":"unaffected"},{"version":"10.11.5","status":"unaffected"},{"version":"10.5.13","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:C/C:H/I:H/A:H","baseScore":9.9,"baseSeverity":"CRITICAL","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"CHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":3.1,"impactScore":6.0}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2025-12-02T04:55:57.705451Z","id":"CVE-2025-12421","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"responsibledisclosure@mattermost.com","type":"Secondary","description":[{"lang":"en","value":"CWE-303"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*","versionStartIncluding":"10.5.0","versionEndExcluding":"10.5.13","matchCriteriaId":"91D99F7F-B4EE-447C-9B77-82DD64B1D83A"},{"vulnerable":true,"criteria":"cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*","versionStartIncluding":"10.11.0","versionEndExcluding":"10.11.5","matchCriteriaId":"A8368192-621C-4043-827E-DB4F6946AD92"},{"vulnerable":true,"criteria":"cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*","versionStartIncluding":"10.12.0","versionEndExcluding":"10.12.2","matchCriteriaId":"ED48D731-6490-4DD5-94D4-EE4555BB93ED"},{"vulnerable":true,"criteria":"cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*","versionStartIncluding":"11.0.0","versionEndExcluding":"11.0.3","matchCriteriaId":"3A288B87-76F2-415B-8462-3D185EB7A9B3"}]}]}],"references":[{"url":"https://mattermost.com/security-updates","source":"responsibledisclosure@mattermost.com","tags":["Vendor Advisory"]}]}