Mattermost vulnerabilities: known CVEs & security history
Mattermost · Communication · 77 tracked CVEs · 0 actively exploited · updated June 2026 · what is a CVE? →
This is the full list of known vulnerabilities (CVEs) across all Mattermost release lines — 77 in total. A CVE here doesn't mean your version is affected — check Mattermost's current status and the safe version to run.
Known Mattermost CVEs
Actively-exploited and most-severe first. Open any CVE for full details.
| CVE | Severity | CVSS | EPSS | Year |
|---|---|---|---|---|
| CVE-2019-20851 | critical | 9.1 | 1% | 2020 |
| CVE-2024-39777 | high | 8.7 | 0% | 2024 |
| CVE-2024-39274 | high | 8.7 | 0% | 2024 |
| CVE-2024-39830 | high | 8.1 | 0% | 2024 |
| CVE-2023-3615 | high | 8.1 | 0% | 2023 |
| CVE-2020-13891 | high | 7.5 | 1% | 2020 |
| CVE-2024-36492 | high | 7.4 | 0% | 2024 |
| CVE-2023-7114 | high | 7.1 | 0% | 2023 |
| CVE-2023-27264 | high | 7.1 | 1% | 2023 |
| CVE-2021-37859 | high | 7.1 | 3% | 2021 |
| CVE-2024-39832 | medium | 6.8 | 0% | 2024 |
| CVE-2023-4107 | medium | 6.7 | 0% | 2023 |
| CVE-2023-2514 | medium | 6.7 | 1% | 2023 |
| CVE-2023-5196 | medium | 6.5 | 1% | 2023 |
| CVE-2023-5195 | medium | 6.5 | 0% | 2023 |
| CVE-2023-2793 | medium | 6.5 | 1% | 2023 |
| CVE-2023-2792 | medium | 6.5 | 1% | 2023 |
| CVE-2023-2787 | medium | 6.5 | 1% | 2023 |
| CVE-2023-2193 | medium | 6.5 | 1% | 2023 |
| CVE-2023-4106 | medium | 6.3 | 0% | 2023 |
| CVE-2023-2788 | medium | 6.2 | 1% | 2023 |
| CVE-2021-37861 | medium | 5.8 | 1% | 2021 |
| CVE-2024-42411 | medium | 5.3 | 0% | 2024 |
| CVE-2024-6428 | medium | 5.3 | 0% | 2024 |
| CVE-2023-5969 | medium | 5.3 | 1% | 2023 |
| CVE-2024-39810 | medium | 4.9 | 0% | 2024 |
| CVE-2023-5968 | medium | 4.9 | 1% | 2023 |
| CVE-2023-5193 | medium | 4.9 | 0% | 2023 |
| CVE-2024-39836 | medium | 4.8 | 0% | 2024 |
| CVE-2024-8071 | medium | 4.7 | 0% | 2024 |
| CVE-2024-40886 | medium | 4.6 | 0% | 2024 |
| CVE-2023-4108 | medium | 4.5 | 1% | 2023 |
| CVE-2024-43813 | medium | 4.3 | 0% | 2024 |
| CVE-2024-32939 | medium | 4.3 | 0% | 2024 |
| CVE-2023-6202 | medium | 4.3 | 0% | 2023 |
| CVE-2023-48369 | medium | 4.3 | 1% | 2023 |
| CVE-2023-48268 | medium | 4.3 | 1% | 2023 |
| CVE-2023-47168 | medium | 4.3 | 0% | 2023 |
| CVE-2023-45223 | medium | 4.3 | 1% | 2023 |
| CVE-2023-43754 | medium | 4.3 | 1% | 2023 |
| CVE-2023-40703 | medium | 4.3 | 1% | 2023 |
| CVE-2023-47865 | medium | 4.3 | 0% | 2023 |
| CVE-2023-5967 | medium | 4.3 | 1% | 2023 |
| CVE-2023-5522 | medium | 4.3 | 0% | 2023 |
| CVE-2023-5160 | medium | 4.3 | 0% | 2023 |
| CVE-2023-2831 | medium | 4.3 | 1% | 2023 |
| CVE-2023-2785 | medium | 4.3 | 1% | 2023 |
| CVE-2023-2791 | medium | 4.3 | 0% | 2023 |
| CVE-2023-2786 | medium | 4.3 | 0% | 2023 |
| CVE-2023-2783 | medium | 4.3 | 0% | 2023 |
| CVE-2023-2808 | medium | 4.3 | 0% | 2023 |
| CVE-2023-27263 | medium | 4.3 | 0% | 2023 |
| CVE-2022-4044 | medium | 4.3 | 1% | 2022 |
| CVE-2022-4019 | medium | 4.3 | 1% | 2022 |
| CVE-2022-2408 | medium | 4.3 | 0% | 2022 |
| CVE-2022-2406 | medium | 4.3 | 1% | 2022 |
| CVE-2022-0708 | medium | 4.3 | 1% | 2022 |
| CVE-2021-37865 | medium | 4.3 | 1% | 2022 |
| CVE-2023-2784 | medium | 4.2 | 0% | 2023 |
| CVE-2023-5159 | low | 3.8 | 0% | 2023 |
| CVE-2026-24661 | low | 3.7 | 0% | 2026 |
| CVE-2021-37860 | low | 3.7 | 1% | 2021 |
| CVE-2024-10214 | low | 3.5 | 0% | 2024 |
| CVE-2023-1562 | low | 3.5 | 0% | 2023 |
| CVE-2022-1003 | low | 3.3 | 0% | 2022 |
| CVE-2024-39807 | low | 3.1 | 0% | 2024 |
| CVE-2024-39361 | low | 3.1 | 0% | 2024 |
| CVE-2023-35075 | low | 3.1 | 0% | 2023 |
| CVE-2023-4105 | low | 3.1 | 0% | 2023 |
| CVE-2023-2797 | low | 3.1 | 0% | 2023 |
| CVE-2022-4045 | low | 3.1 | 1% | 2022 |
| CVE-2024-29977 | low | 2.7 | 0% | 2024 |
| CVE-2024-39353 | low | 2.7 | 0% | 2024 |
| CVE-2024-36257 | low | 2.7 | 0% | 2024 |
| CVE-2023-5194 | low | 2.7 | 0% | 2023 |
| CVE-2021-37864 | low | 2.6 | 1% | 2022 |
| CVE-2022-1002 | low | 2 | 1% | 2022 |
Is my Mattermost version affected?
The list above spans every release. To know whether your version is affected — and the minimum safe version to upgrade to — check it directly.
Check your Mattermost version → · Monitor Mattermost for new CVEs →
Mattermost vulnerabilities — frequently asked
How many known vulnerabilities does Mattermost have?
IsItPatched tracks 77 CVEs for Mattermost. 1 is critical-severity and 9 high-severity. These span every release line — what matters is whether the version you run is affected.
Does Mattermost have any actively-exploited vulnerabilities?
None of Mattermost's tracked CVEs are currently in CISA's KEV catalog — but new ones can be added at any time, so keep your version current.
What is the most severe Mattermost vulnerability?
Among tracked issues, CVE-2019-20851 (CRITICAL, CVSS 9.1) ranks highest — a Path traversal weakness.
Is Mattermost safe to use?
It depends on the version. The latest supported Mattermost release clears the known issues; older versions may still be affected. Check the exact version you run for a verdict.
CVE data aggregated from NVD, CISA KEV and EPSS (FIRST.org). Related: Mattermost security status · Mattermost end-of-life · actively-exploited CVEs. Always verify against Mattermost's advisories — see our disclaimer.