{"schema_version":1,"title":"Mattermost Server vulnerabilities","summary":"Junglewise Threat Intelligence has tracked 72 vulnerabilities in Mattermost Server: 3 in the last 7 days and 25 in the last 90 days, 0 of them critical and 0 exploited in the wild. The most recent, CVE-2026-96260, was published on 22 September 2026.","url":"https://junglewise.ai/threats/technologies/server-public","json_url":"https://junglewise.ai/threats/technologies/server-public.json","publisher":"Junglewise Threat Intelligence","license":"CC-BY-4.0","license_url":"https://creativecommons.org/licenses/by/4.0/","attribution":"Junglewise Threat Intelligence, https://junglewise.ai/threats/technologies/server-public","sources":"NVD, GitHub Security Advisories, OSV, the CISA Known Exploited Vulnerabilities catalog, FIRST EPSS and vendor advisories","kind":"technology","counts":{"high":9,"all_time":72,"critical":0,"exploited":0,"last_7_days":3,"last_30_days":15,"last_90_days":25,"last_365_days":72},"latest":[{"cve":"CVE-2026-96260","cvss":6.5,"epss":0.0041,"slug":"cve-2026-96260-mattermost-versions-11-9-x-11-9-1-11-8-x-11-8-5-11-7-x-11-7-10-11","title":"Mattermost memory exhaustion in CSRF validation for plugin endpoints","severity":"medium","exploited":false,"published_at":"2026-09-22T21:17:35.027+00:00","url":"https://junglewise.ai/threats/cve-2026-96260-mattermost-versions-11-9-x-11-9-1-11-8-x-11-8-5-11-7-x-11-7-10-11"},{"cve":"CVE-2026-96259","cvss":5.5,"epss":0.0026,"slug":"cve-2026-96259-mattermost-versions-11-9-x-11-9-1-11-8-x-11-8-5-11-7-x-11-7-10-11","title":"Mattermost internal-connection filter bypass in OAuth endpoints","severity":"medium","exploited":false,"published_at":"2026-09-22T21:17:34.91+00:00","url":"https://junglewise.ai/threats/cve-2026-96259-mattermost-versions-11-9-x-11-9-1-11-8-x-11-8-5-11-7-x-11-7-10-11"},{"cve":"CVE-2026-95666","cvss":4.3,"epss":0.0036,"slug":"cve-2026-95666-mattermost-versions-11-9-x-11-9-1-11-8-x-11-8-5-11-7-x-11-7-10-11","title":"Mattermost denial of service via unbounded post ID array","severity":"medium","exploited":false,"published_at":"2026-09-22T14:17:21.437+00:00","url":"https://junglewise.ai/threats/cve-2026-95666-mattermost-versions-11-9-x-11-9-1-11-8-x-11-8-5-11-7-x-11-7-10-11"},{"cve":"CVE-2026-91181","cvss":6.5,"epss":0.0039,"slug":"cve-2026-91181-mattermost-information-disclosure-in-data-retention-teams","title":"Mattermost information disclosure in data retention teams endpoint","severity":"medium","exploited":false,"published_at":"2026-09-14T22:16:59.643+00:00","url":"https://junglewise.ai/threats/cve-2026-91181-mattermost-information-disclosure-in-data-retention-teams"},{"cve":"CVE-2026-12985","cvss":6.8,"epss":0.0028,"slug":"cve-2026-12985-mattermost-oauth-redirect-uri-validation-bypass","title":"Mattermost OAuth redirect URI validation bypass","severity":"medium","exploited":false,"published_at":"2026-09-14T15:17:04.27+00:00","url":"https://junglewise.ai/threats/cve-2026-12985-mattermost-oauth-redirect-uri-validation-bypass"},{"cve":"CVE-2026-86349","cvss":4.3,"epss":0.0036,"slug":"cve-2026-86349-mattermost-markdown-parser-denial-of-service","title":"Mattermost Markdown parser denial of service","severity":"medium","exploited":false,"published_at":"2026-09-14T14:17:15.687+00:00","url":"https://junglewise.ai/threats/cve-2026-86349-mattermost-markdown-parser-denial-of-service"},{"cve":"CVE-2026-86348","cvss":4.3,"epss":0.0036,"slug":"cve-2026-86348-mattermost-denial-of-service-via-handler-panic-in-post-action","title":"Mattermost denial of service via handler panic in post-action request","severity":"medium","exploited":false,"published_at":"2026-09-14T14:17:15.57+00:00","url":"https://junglewise.ai/threats/cve-2026-86348-mattermost-denial-of-service-via-handler-panic-in-post-action"},{"cve":"CVE-2026-82920","cvss":5.5,"epss":0.0026,"slug":"cve-2026-82920-mattermost-authorization-bypass-in-access-control-policy-endpoint","title":"Mattermost authorization bypass in access control policy endpoint","severity":"medium","exploited":false,"published_at":"2026-09-14T14:17:13.01+00:00","url":"https://junglewise.ai/threats/cve-2026-82920-mattermost-authorization-bypass-in-access-control-policy-endpoint"},{"cve":"CVE-2026-8821","cvss":7.1,"epss":0.0029,"slug":"cve-2026-8821-mattermost-authorization-bypass-in-playbook-creation","title":"Mattermost authorization bypass in playbook creation","severity":"high","exploited":false,"published_at":"2026-09-14T11:17:06.153+00:00","url":"https://junglewise.ai/threats/cve-2026-8821-mattermost-authorization-bypass-in-playbook-creation"},{"cve":"CVE-2026-5132","cvss":6.5,"epss":0.0041,"slug":"cve-2026-5132-mattermost-sdp-message-decompression-denial-of-service","title":"Mattermost SDP message decompression denial of service","severity":"medium","exploited":false,"published_at":"2026-09-14T11:17:04.14+00:00","url":"https://junglewise.ai/threats/cve-2026-5132-mattermost-sdp-message-decompression-denial-of-service"},{"cve":"CVE-2026-14259","cvss":4.3,"epss":0.0015,"slug":"cve-2026-14259-mattermost-board-creation-permissions-bypass-on-archive-import","title":"Mattermost board creation permissions bypass on archive import","severity":"medium","exploited":false,"published_at":"2026-09-14T11:17:03.307+00:00","url":"https://junglewise.ai/threats/cve-2026-14259-mattermost-board-creation-permissions-bypass-on-archive-import"},{"cve":"CVE-2026-12882","cvss":4.3,"epss":0.0021,"slug":"cve-2026-12882-mattermost-redos-in-markdown-autolink-parsing","title":"Mattermost ReDoS in Markdown autolink parsing","severity":"medium","exploited":false,"published_at":"2026-09-14T11:17:03.05+00:00","url":"https://junglewise.ai/threats/cve-2026-12882-mattermost-redos-in-markdown-autolink-parsing"},{"cve":"CVE-2026-11993","cvss":4.3,"epss":0.0021,"slug":"cve-2026-11993-mattermost-file-upload-goroutine-exhaustion-denial-of-service","title":"Mattermost file upload goroutine exhaustion denial of service","severity":"medium","exploited":false,"published_at":"2026-09-14T11:17:02.8+00:00","url":"https://junglewise.ai/threats/cve-2026-11993-mattermost-file-upload-goroutine-exhaustion-denial-of-service"},{"cve":"CVE-2026-10556","cvss":5.3,"epss":0.0025,"slug":"cve-2026-10556-mattermost-microsoft-calendar-plugin-denial-of-service-via","title":"Mattermost Microsoft Calendar plugin denial of service via webhook validation bypass","severity":"medium","exploited":false,"published_at":"2026-09-14T11:17:02.59+00:00","url":"https://junglewise.ai/threats/cve-2026-10556-mattermost-microsoft-calendar-plugin-denial-of-service-via"},{"cve":"CVE-2026-10542","cvss":5,"epss":0.0013,"slug":"cve-2026-10542-mattermost-authorization-bypass-in-channel-action-update","title":"Mattermost authorization bypass in channel action update","severity":"medium","exploited":false,"published_at":"2026-09-14T11:17:02.447+00:00","url":"https://junglewise.ai/threats/cve-2026-10542-mattermost-authorization-bypass-in-channel-action-update"},{"cve":"CVE-2026-9859","cvss":6.5,"epss":0.0034,"slug":"cve-2026-9859-mattermost-privilege-escalation-in-board-channel-reassignment","title":"Mattermost privilege escalation in board channel reassignment","severity":"medium","exploited":false,"published_at":"2026-08-17T22:17:27.343+00:00","url":"https://junglewise.ai/threats/cve-2026-9859-mattermost-privilege-escalation-in-board-channel-reassignment"},{"cve":"CVE-2026-10819","cvss":6.5,"slug":"cve-2026-10819-mattermost-denial-of-service-via-animated-gif-emoji-uploads","title":"Mattermost denial of service via animated GIF emoji uploads","severity":"medium","exploited":false,"published_at":"2026-07-27T15:16:46.77+00:00","url":"https://junglewise.ai/threats/cve-2026-10819-mattermost-denial-of-service-via-animated-gif-emoji-uploads"},{"cve":"CVE-2026-9824","cvss":4.3,"slug":"cve-2026-9824-mattermost-missing-authorization-in-share-channel-autocomplete","title":"Mattermost missing authorization in share-channel autocomplete handler","severity":"medium","exploited":false,"published_at":"2026-07-13T11:16:28.317+00:00","url":"https://junglewise.ai/threats/cve-2026-9824-mattermost-missing-authorization-in-share-channel-autocomplete"},{"cve":"CVE-2026-9820","cvss":3.8,"slug":"cve-2026-9820-mattermost-information-disclosure-in-scheme-teams-api-endpoint","title":"Mattermost information disclosure in scheme teams API endpoint","severity":"low","exploited":false,"published_at":"2026-07-13T11:16:28.203+00:00","url":"https://junglewise.ai/threats/cve-2026-9820-mattermost-information-disclosure-in-scheme-teams-api-endpoint"},{"cve":"CVE-2026-9708","cvss":4.9,"slug":"cve-2026-9708-mattermost-authorization-bypass-in-incoming-webhooks","title":"Mattermost authorization bypass in incoming webhooks","severity":"medium","exploited":false,"published_at":"2026-07-13T09:16:25.253+00:00","url":"https://junglewise.ai/threats/cve-2026-9708-mattermost-authorization-bypass-in-incoming-webhooks"},{"cve":"CVE-2026-9597","cvss":5.4,"slug":"cve-2026-9597-mattermost-authentication-bypass-for-deactivated-guest-accounts","title":"Mattermost authentication bypass for deactivated guest accounts via magic-link","severity":"medium","exploited":false,"published_at":"2026-07-13T09:16:25.137+00:00","url":"https://junglewise.ai/threats/cve-2026-9597-mattermost-authentication-bypass-for-deactivated-guest-accounts"},{"cve":"CVE-2026-9571","cvss":5.9,"slug":"cve-2026-9571-mattermost-server-oauth-token-invalidation-failure-on-account","title":"Mattermost Server OAuth token invalidation failure on account deactivation","severity":"medium","exploited":false,"published_at":"2026-07-13T09:16:25.017+00:00","url":"https://junglewise.ai/threats/cve-2026-9571-mattermost-server-oauth-token-invalidation-failure-on-account"},{"cve":"CVE-2026-10106","cvss":6.5,"slug":"cve-2026-10106-mattermost-incorrect-authorization-in-interactive-post-actions","title":"Mattermost incorrect authorization in interactive post actions","severity":"medium","exploited":false,"published_at":"2026-07-13T09:16:23.77+00:00","url":"https://junglewise.ai/threats/cve-2026-10106-mattermost-incorrect-authorization-in-interactive-post-actions"},{"cve":"CVE-2026-10103","cvss":4.3,"slug":"cve-2026-10103-mattermost-server-authorization-bypass-in-shared-channel-sync","title":"Mattermost Server authorization bypass in shared channel sync","severity":"medium","exploited":false,"published_at":"2026-07-13T09:16:23.653+00:00","url":"https://junglewise.ai/threats/cve-2026-10103-mattermost-server-authorization-bypass-in-shared-channel-sync"},{"cve":"CVE-2026-10085","cvss":5.4,"slug":"cve-2026-10085-mattermost-authorization-bypass-in-channel-patch-api","title":"Mattermost authorization bypass in channel patch API","severity":"medium","exploited":false,"published_at":"2026-07-13T09:16:22.447+00:00","url":"https://junglewise.ai/threats/cve-2026-10085-mattermost-authorization-bypass-in-channel-patch-api"}],"weekly":[{"week":"2026-07-06","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-07-13","critical":0,"exploited":0,"vulnerabilities":8},{"week":"2026-07-20","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-07-27","critical":0,"exploited":0,"vulnerabilities":1},{"week":"2026-08-03","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-08-10","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-08-17","critical":0,"exploited":0,"vulnerabilities":1},{"week":"2026-08-24","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-08-31","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-09-07","critical":0,"exploited":0,"vulnerabilities":0},{"week":"2026-09-14","critical":0,"exploited":0,"vulnerabilities":12},{"week":"2026-09-21","critical":0,"exploited":0,"vulnerabilities":3},{"week":"2026-09-28","critical":0,"exploited":0,"vulnerabilities":0}],"related":[{"name":"Mattermost Desktop App","slug":"desktop-app","vulnerabilities":14,"url":"https://junglewise.ai/threats/technologies/desktop-app"},{"name":"Mattermost","slug":"mattermost","vulnerabilities":9,"url":"https://junglewise.ai/threats/technologies/mattermost"},{"name":"Mattermost Plugins","slug":"mattermost-plugins","vulnerabilities":5,"url":"https://junglewise.ai/threats/technologies/mattermost-plugins"},{"name":"Mattermost GitHub Plugin for Mattermost","slug":"github-plugin","vulnerabilities":3,"url":"https://junglewise.ai/threats/technologies/github-plugin"}],"technology":{"hub":true,"name":"Mattermost Server","slug":"server-public","vendor":{"name":"Mattermost","slug":"mattermost","url":"https://junglewise.ai/threats/vendors/mattermost"},"aliases":["mattermost-server"],"category":"library","homepage":"https://mattermost.com/","repo_url":"https://github.com/mattermost/mattermost","description":"Server Public is a library containing shared components and utilities for the Mattermost server.","url":"https://junglewise.ai/threats/technologies/server-public"},"most_severe":[{"cve":"CVE-2026-7387","cvss":8.8,"epss":0.0042,"slug":"cve-2026-7387-mattermost-privilege-escalation-in-group-syncable-link-and-patch","title":"Mattermost privilege escalation in group syncable link and patch endpoints","severity":"high","exploited":false,"published_at":"2026-06-12T17:16:27.653+00:00","url":"https://junglewise.ai/threats/cve-2026-7387-mattermost-privilege-escalation-in-group-syncable-link-and-patch"},{"cve":"CVE-2026-6346","cvss":8.7,"epss":0.0041,"slug":"cve-2026-6346-mattermost-sensitive-information-disclosure-in-support-packet","title":"Mattermost sensitive information disclosure in support packet generation","severity":"high","exploited":false,"published_at":"2026-05-18T09:16:24+00:00","url":"https://junglewise.ai/threats/cve-2026-6346-mattermost-sensitive-information-disclosure-in-support-packet"},{"cve":"CVE-2026-4858","cvss":8,"epss":0.004,"slug":"cve-2026-4858-mattermost-path-traversal-in-integration-action-url","title":"Mattermost path traversal in integration action URL","severity":"high","exploited":false,"published_at":"2026-05-21T09:16:30.143+00:00","url":"https://junglewise.ai/threats/cve-2026-4858-mattermost-path-traversal-in-integration-action-url"},{"cve":"CVE-2026-6961","cvss":7.6,"epss":0.0045,"slug":"cve-2026-6961-mattermost-path-traversal-in-shared-channel-file-sync","title":"Mattermost path traversal in shared channel file sync","severity":"high","exploited":false,"published_at":"2026-06-12T17:16:27.41+00:00","url":"https://junglewise.ai/threats/cve-2026-6961-mattermost-path-traversal-in-shared-channel-file-sync"},{"cve":"CVE-2026-6347","cvss":7.6,"epss":0.0043,"slug":"cve-2026-6347-mattermost-calls-plugin-information-disclosure-in-support-packets","title":"Mattermost Calls plugin information disclosure in support packets","severity":"high","exploited":false,"published_at":"2026-05-18T09:16:24.143+00:00","url":"https://junglewise.ai/threats/cve-2026-6347-mattermost-calls-plugin-information-disclosure-in-support-packets"},{"cve":"CVE-2026-5740","cvss":7.5,"epss":0.0057,"slug":"cve-2026-5740-mattermost-server-denial-of-service-via-msgpack-websocket-frames","title":"Mattermost Server denial of service via msgpack WebSocket frames","severity":"high","exploited":false,"published_at":"2026-05-22T11:16:23.163+00:00","url":"https://junglewise.ai/threats/cve-2026-5740-mattermost-server-denial-of-service-via-msgpack-websocket-frames"},{"cve":"CVE-2026-5308","cvss":7.5,"epss":0.0045,"slug":"cve-2026-5308-mattermost-denial-of-service-in-plugin-http-endpoints","title":"Mattermost denial of service in plugin HTTP endpoints","severity":"high","exploited":false,"published_at":"2026-05-22T11:16:23.047+00:00","url":"https://junglewise.ai/threats/cve-2026-5308-mattermost-denial-of-service-in-plugin-http-endpoints"},{"cve":"CVE-2026-8821","cvss":7.1,"epss":0.0029,"slug":"cve-2026-8821-mattermost-authorization-bypass-in-playbook-creation","title":"Mattermost authorization bypass in playbook creation","severity":"high","exploited":false,"published_at":"2026-09-14T11:17:06.153+00:00","url":"https://junglewise.ai/threats/cve-2026-8821-mattermost-authorization-bypass-in-playbook-creation"},{"cve":"CVE-2026-3473","cvss":7.1,"epss":0.0025,"slug":"cve-2026-3473-mattermost-server-authorization-bypass-in-boards-api","title":"Mattermost Server authorization bypass in Boards API","severity":"high","exploited":false,"published_at":"2026-05-22T11:16:22.477+00:00","url":"https://junglewise.ai/threats/cve-2026-3473-mattermost-server-authorization-bypass-in-boards-api"},{"cve":"CVE-2026-12985","cvss":6.8,"epss":0.0028,"slug":"cve-2026-12985-mattermost-oauth-redirect-uri-validation-bypass","title":"Mattermost OAuth redirect URI validation bypass","severity":"medium","exploited":false,"published_at":"2026-09-14T15:17:04.27+00:00","url":"https://junglewise.ai/threats/cve-2026-12985-mattermost-oauth-redirect-uri-validation-bypass"}],"generated_at":"2026-09-28T03:07:00.154823+00:00"}