Technology · Mattermost
Mattermost vulnerabilities
Updated . Rebuilt every hour.
Junglewise Threat Intelligence has tracked 9 vulnerabilities in Mattermost: 0 in the last 7 days and 6 in the last 90 days, 0 of them critical and 0 exploited in the wild. The most recent, CVE-2026-14344, was published on 14 September 2026.
- Last 7 days
- 0
- Last 90 days
- 6
- Critical, all time
- 0
- Exploited in the wild
- 0
About Mattermost
Mattermost is an open-source, self-hosted online chat service with file sharing, search, and integrations.
Latest Mattermost vulnerabilities
- CVE-2026-14344: Mattermost permission bypass in board creationmediumCVSS 4.3EPSS 0.1%
- CVE-2026-9816: Mattermost privilege escalation via BoardMember.Scheme validation bypasshighCVSS 8.3EPSS 0.4%
- CVE-2026-7521: Mattermost path traversal in file deletion endpointmediumCVSS 5.5
- CVE-2026-10600: Mattermost resource exhaustion in document content extractionmediumCVSS 4.3
- CVE-2026-6541: Mattermost authorization bypass in Playbook metric configurationmediumCVSS 4.3
- CVE-2026-6850: Mattermost ReDoS in client-side markdown parsermediumCVSS 6.5
- CVE-2026-9162: Mattermost insufficient session expiration in WebSocket connectionsmediumCVSS 4.3EPSS 0.3%
- CVE-2026-6673: Mattermost authentication bypass in Atlassian Connect callbackmediumCVSS 6.4EPSS 0.3%
- CVE-2026-5139: Mattermost missing authorization in GitLab connect commandmediumCVSS 5.4EPSS 0.3%
Most severe Mattermost vulnerabilities
Exploited in the wild first, then by severity and CVSS score.
- CVE-2026-9816: Mattermost privilege escalation via BoardMember.Scheme validation bypasshighCVSS 8.3EPSS 0.4%
- CVE-2026-6850: Mattermost ReDoS in client-side markdown parsermediumCVSS 6.5
- CVE-2026-6673: Mattermost authentication bypass in Atlassian Connect callbackmediumCVSS 6.4EPSS 0.3%
- CVE-2026-7521: Mattermost path traversal in file deletion endpointmediumCVSS 5.5
- CVE-2026-5139: Mattermost missing authorization in GitLab connect commandmediumCVSS 5.4EPSS 0.3%
- CVE-2026-9162: Mattermost insufficient session expiration in WebSocket connectionsmediumCVSS 4.3EPSS 0.3%
- CVE-2026-14344: Mattermost permission bypass in board creationmediumCVSS 4.3EPSS 0.1%
- CVE-2026-10600: Mattermost resource exhaustion in document content extractionmediumCVSS 4.3
- CVE-2026-6541: Mattermost authorization bypass in Playbook metric configurationmediumCVSS 4.3
Vulnerabilities per week
The last 13 weeks, by the week each vulnerability was published.
| Week of | Bar | Vulns | Critical |
|---|---|---|---|
| 29 Jun 2026 | 0 | 0 | |
| 6 Jul 2026 | 0 | 0 | |
| 13 Jul 2026 | 2 | 0 | |
| 20 Jul 2026 | 0 | 0 | |
| 27 Jul 2026 | 2 | 0 | |
| 3 Aug 2026 | 0 | 0 | |
| 10 Aug 2026 | 0 | 0 | |
| 17 Aug 2026 | 1 | 0 | |
| 24 Aug 2026 | 0 | 0 | |
| 31 Aug 2026 | 0 | 0 | |
| 7 Sep 2026 | 0 | 0 | |
| 14 Sep 2026 | 1 | 0 | |
| 21 Sep 2026 | 0 | 0 |
How this is built
Junglewise Threat Intelligence collects vulnerabilities from NVD, GitHub Security Advisories, OSV, the CISA Known Exploited Vulnerabilities catalog, FIRST EPSS and vendor advisories, and matches each one to the technologies and vendors it affects. Dates are the date a vulnerability was published, in UTC.
The pages are rebuilt from the database every hour. Frozen weekly and monthly reports never change once published, so they can be cited.
Use this data
The same data is at https://junglewise.ai/threats/technologies/mattermost.json, for scripts and language models. It is free to reuse under CC BY 4.0 with a link back to this page.
Cite as: Junglewise Threat Intelligence, "Mattermost vulnerabilities", https://junglewise.ai/threats/technologies/mattermost, 26 September 2026.