{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-3590","assignerOrgId":"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee","state":"PUBLISHED","assignerShortName":"Mattermost","dateReserved":"2026-03-05T11:34:57.712Z","datePublished":"2026-04-15T11:00:14.880Z","dateUpdated":"2026-04-15T14:00:27.030Z"},"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Mattermost","vendor":"Mattermost","versions":[{"lessThanOrEqual":"10.11.12","status":"affected","version":"10.11.0","versionType":"semver"},{"lessThanOrEqual":"11.5.0","status":"affected","version":"11.5.0","versionType":"semver"},{"lessThanOrEqual":"11.4.2","status":"affected","version":"11.4.0","versionType":"semver"},{"lessThanOrEqual":"11.3.2","status":"affected","version":"11.3.0","versionType":"semver"},{"version":"11.6.0","status":"unaffected"},{"version":"10.11.13","status":"unaffected"},{"version":"11.5.1","status":"unaffected"},{"version":"11.4.3","status":"unaffected"},{"version":"11.3.3","status":"unaffected"}]}],"credits":[{"lang":"en","type":"finder","value":"Edgar Bellot Micó"}],"descriptions":[{"lang":"en","value":"Mattermost versions 10.11.x <= 10.11.12, 11.5.x <= 11.5.0, 11.4.x <= 11.4.2, 11.3.x <= 11.3.2 fail to enforce atomic single-use consumption of guest magic link tokens, which allows an attacker with access to a valid magic link to establish multiple independent authenticated sessions via concurrent requests.. Mattermost Advisory ID: MMSA-2026-00624"}],"metrics":[{"cvssV3_1":{"attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"LOW","integrityImpact":"LOW","availabilityImpact":"NONE","version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","baseSeverity":"MEDIUM","baseScore":6.5},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"lang":"en","type":"CWE","description":"CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition","cweId":"CWE-367"}]}],"references":[{"url":"https://mattermost.com/security-updates","name":"MMSA-2026-00624","tags":["vendor-advisory"]}],"solutions":[{"value":"Update Mattermost to versions 11.6.0, 10.11.13, 11.5.1, 11.4.3, 11.3.3 or higher.","lang":"en"}],"source":{"advisory":"MMSA-2026-00624","defect":["https://mattermost.atlassian.net/browse/MM-67791"],"discovery":"EXTERNAL"},"title":"Race Condition in Guest Magic Link Authentication Allows Token Reuse","providerMetadata":{"orgId":"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee","shortName":"Mattermost","dateUpdated":"2026-04-15T11:00:14.880Z"},"x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-04-15T14:00:15.919479Z","id":"CVE-2026-3590","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-04-15T14:00:27.030Z"}}]}}