{"id":"CVE-2026-75588","summary":"Mattermost Desktop App plugin popout scheme validation bypass","details":"Mattermost Desktop App versions \u003c=6.2 6.2.2.0 fail to validate the URL scheme when checking whether a target URL is internal to the connected server, which allows a network-positioned attacker to load a plugin popout window over an insecure connection via a link using a downgraded URL scheme. Mattermost Advisory ID: MMSA-2026-00717","modified":"2026-10-15T02:47:33.176108758Z","published":"2026-09-17T15:09:40.829Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/75xxx/CVE-2026-75588.json","unresolved_ranges":[{"source":"AFFECTED_FIELD","extracted_events":[{"last_affected":"6.2.2"}]}],"cna_assigner":"Mattermost","cwe_ids":["CWE-1287"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/75xxx/CVE-2026-75588.json"},{"type":"ADVISORY","url":"https://mattermost.com/security-updates"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-75588"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/mattermost/desktop","events":[{"introduced":"200c274b361a2dcb7d7e8208adc44bdcd4645616"},{"fixed":"99b6258eda51936ee4004a4e0175db06d65cc106"}],"database_specific":{"source":"CPE_RANGE","cpe":"cpe:2.3:a:mattermost:mattermost_desktop:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"6.2.0"},{"fixed":"6.2.3"}]}}],"versions":["v6.2.3-rc.2","v6.2.3-rc.1","v6.2.2-mas.1","v6.2.2","v6.2.2-rc.1","v6.2.1-mas.2","v6.2.1","v6.2.1-mas.1","v6.2.1-rc.1","v6.2.0-mas.1","v6.2.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-75588.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:L/A:N"}]}