{"id":"CVE-2026-1628","state":"PUBLISHED","title":"Mattermost allows external websites to open within the app, exposing preload functionality to non-trusted sites.","description":"Mattermost Desktop App versions <=5.13.3 fail to attach listeners restricting navigation to external sites within the Mattermost app which allows a malicious server to expose preload script functionality to untrusted servers via having a user open an external link in their Mattermost server. Mattermost Advisory ID: MMSA-2026-00596","publishedAt":"2026-03-02T13:24:21.391Z","updatedAt":"2026-03-02T14:58:30.546Z","severity":{"score":4.6,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N","source":"Mattermost"},"assigner":"Mattermost","products":["Mattermost Mattermost"],"affected":[{"vendor":"Mattermost","product":"Mattermost","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"5.13.3","versionType":"semver"},{"version":"5.13.4.0","status":"unaffected"}]}],"references":["https://mattermost.com/security-updates"],"weaknesses":["CWE-829"],"ingestedAt":"2026-10-29T20:11:10.572Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/1xxx/CVE-2026-1628.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-1628","state":"PUBLISHED","datePublished":"2026-03-02T13:24:21.391Z","dateUpdated":"2026-03-02T14:58:30.546Z","assignerShortName":"Mattermost","assignerOrgId":"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee","dateReserved":"2026-01-29T15:14:51.993Z"},"containers":{"cna":{"title":"Mattermost allows external websites to open within the app, exposing preload functionality to non-trusted sites.","descriptions":[{"lang":"en","value":"Mattermost Desktop App versions <=5.13.3 fail to attach listeners restricting navigation to external sites within the Mattermost app which allows a malicious server to expose preload script functionality to untrusted servers via having a user open an external link in their Mattermost server. Mattermost Advisory ID: MMSA-2026-00596"}],"affected":[{"vendor":"Mattermost","product":"Mattermost","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"5.13.3","versionType":"semver"},{"version":"5.13.4.0","status":"unaffected"}]}],"references":[{"url":"https://mattermost.com/security-updates","name":"MMSA-2026-00596","tags":["vendor-advisory"]}],"metrics":[{"cvssV3_1":{"attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"REQUIRED","scope":"UNCHANGED","confidentialityImpact":"LOW","integrityImpact":"LOW","availabilityImpact":"NONE","version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N","baseSeverity":"MEDIUM","baseScore":4.6},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-829","lang":"en","type":"CWE","description":"CWE-829: Inclusion of Functionality from Untrusted Control Sphere"}]}],"providerMetadata":{"shortName":"Mattermost","orgId":"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee","dateUpdated":"2026-03-02T13:24:21.391Z"},"credits":[{"lang":"en","type":"finder","value":"N/A"}],"solutions":[{"value":"Update Mattermost Desktop App to versions 5.13.4.0 or higher.","lang":"en"}],"source":{"advisory":"MMSA-2026-00596","defect":["https://mattermost.atlassian.net/browse/MM-67374"],"discovery":"EXTERNAL"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-03-02T14:57:20.504558Z","id":"CVE-2026-1628","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":"2026-03-02T14:58:30.546Z"}}]}}}