{"id":"CVE-2026-86348","aliases":["EUVD-2026-77481","GHSA-hw33-g6h4-vc78"],"status":"published","title":"MS Calendar plugin: unrecovered handler panics from malformed post-action requests could crash the plugin process","description":"Mattermost versions \u003c=11.9 11.0.9 11.4.8 11.7.7 10.22.11.0 fail to recover from handler panics, which allows an authenticated user to crash the plugin via a post-action request with an unexpected field type.. Mattermost Advisory ID: MMSA-2026-00701","severity":{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00367,"percentile":0.30804,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-704"],"published":"2026-09-14T13:52:24Z","modified":"2026-10-28T02:31:03Z","products":[{"vendor":"mattermost","product":"mattermost"},{"vendor":"mattermost","product":"mattermost_server"}],"references":[{"url":"https://mattermost.com/security-updates","tags":["vendor-advisory","Vendor Advisory","advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-86348","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-hw33-g6h4-vc78"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/86xxx/CVE-2026-86348.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-86348","title":"MS Calendar plugin: unrecovered handler panics from malformed post-action requests could crash the plugin process","description":"Mattermost versions \u003c=11.9 11.0.9 11.4.8 11.7.7 10.22.11.0 fail to recover from handler panics, which allows an authenticated user to crash the plugin via a post-action request with an unexpected field type.. Mattermost Advisory ID: MMSA-2026-00701","status":"published","published":"2026-09-14T13:52:24.602Z","modified":"2026-09-14T19:23:01.298Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"cna"}],"cwes":["CWE-704"],"updated_at":"2026-11-02T13:49:42.666099Z"}],"euvd":[{"id":"EUVD-2026-77481","description":"Mattermost versions \u003c=11.9 11.0.9 11.4.8 11.7.7 10.22.11.0 fail to recover from handler panics, which allows an authenticated user to crash the plugin via a post-action request with an unexpected field type.. Mattermost Advisory ID: MMSA-2026-00701","status":"published","published":"2026-09-14T13:52:24Z","modified":"2026-09-14T19:23:01Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"updated_at":"2026-11-02T17:28:19.383429Z"}],"ghsa":[{"id":"GHSA-hw33-g6h4-vc78","title":"Mattermost versions \u003c=11.9 11.0.9 11.4.8 11.7.7 10.22.11.0 fail to recover from handler panics,...","description":"Mattermost versions \u003c=11.9 11.0.9 11.4.8 11.7.7 10.22.11.0 fail to recover from handler panics, which allows an authenticated user to crash the plugin via a post-action request with an unexpected field type.. Mattermost Advisory ID: MMSA-2026-00701","status":"published","published":"2026-09-14T15:32:46Z","modified":"2026-09-14T15:32:47Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"cwes":["CWE-704"],"updated_at":"2026-11-02T15:11:50.762382Z"}],"nvd":[{"id":"CVE-2026-86348","description":"Mattermost versions \u003c=11.9 11.0.9 11.4.8 11.7.7 10.22.11.0 fail to recover from handler panics, which allows an authenticated user to crash the plugin via a post-action request with an unexpected field type.. Mattermost Advisory ID: MMSA-2026-00701","status":"published","published":"2026-09-14T14:17:15.57Z","modified":"2026-10-14T19:28:53.743Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"secondary"}],"cwes":["CWE-704"],"updated_at":"2026-11-02T14:12:46.980627Z"}],"osv":[{"id":"CVE-2026-86348","title":"MS Calendar plugin: unrecovered handler panics from malformed post-action requests could crash the plugin process","description":"Mattermost versions \u003c=11.9 11.0.9 11.4.8 11.7.7 10.22.11.0 fail to recover from handler panics, which allows an authenticated user to crash the plugin via a post-action request with an unexpected field type.. Mattermost Advisory ID: MMSA-2026-00701","status":"published","published":"2026-09-14T13:52:24.602Z","modified":"2026-10-28T02:31:03.032242398Z","cvss":[{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"cwes":["CWE-704"],"updated_at":"2026-11-02T15:45:18.825071Z"}]}}