Mattermost Server
Vendor:
First CVE: Jun 19, 2020 · Active for 6 years
452
Total CVEs
More Total CVEs than 100% of tracked products
64.6
Avg CVEs / Year
Higher CVE frequency than 99% of tracked products
5.6
Avg CVSS
Higher Avg CVSS than 16% of tracked products
0.0%
KEV Rate
Bottom 1%
Trends Over Time
The number and severity of CVEs published that impact Mattermost Server over time
Volume of CVEsAvg CVSS Base Score
First CVE
Jun 19, 2020
6 years ago
Most Recent CVE
Jul 13, 2026
13 days ago
CVE Severity & Scoring
Mattermost Server452 CVEs
9%
69%
18%
All CVEs352,719 CVEs
45%
40%
11%
LowMediumHighCritical
Attack Vector
Local5 (1.1%)
Network447 (98.9%)
Unknown0 (0.0%)
Physical0 (0.0%)
Adjacent Network0 (0.0%)
Attack Complexity
Low431 (95.4%)
High21 (4.6%)
Unknown0 (0.0%)
User Interaction
None391 (86.5%)
Unknown0 (0.0%)
Required61 (13.5%)
Privileges Required
Low247 (54.6%)
High52 (11.5%)
None153 (33.8%)
Unknown0 (0.0%)
Top CVEs
Signals from CVEs in this product scope (452 CVEs).
452 CVEs · Highest risk first
| CVE | Published | CVSS | Risk | KEV | Exploit |
|---|---|---|---|---|---|
CVE-2026-4858CRITICAL Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to check integration URL for path traversal which allows an malicious authenticat | May 21, 2026 | 9.9 | 40 | NO | NO |
CVE-2025-25279HIGH Mattermost versions 10.4.x <= 10.4.1, 9.11.x <= 9.11.7, 10.3.x <= 10.3.2, 10.2.x <= 10.2.2 fail to properly validate board blocks when importing boards which allows an attacker cou | Feb 24, 2025 | 7.5 | 36 | NO | NO |
CVE-2026-6346HIGH Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to sanitize sensitive configuration fields before including them in support packet generation, whic | May 18, 2026 | 8.7 | 34 | NO | NO |
CVE-2025-12419CRITICAL Mattermost versions 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12, 11.0.x <= 11.0.3 fail to properly validate OAuth state tokens during OpenID Connect authentication wh | Nov 27, 2025 | 9.9 | 34 | NO | NO |
CVE-2026-6850MEDIUM Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to validate the length and content of message attachment field values, which allows an authenticate | Jul 13, 2026 | 6.5 | 33 | NO | NO |
CVE-2026-7387HIGH Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 Mattermost fails to require role-management authorization when setting the scheme_a | Jun 12, 2026 | 8.8 | 33 | NO | NO |
CVE-2025-12421CRITICAL Mattermost versions 11.0.x <= 11.0.2, 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to to verify that the token used during the code exchange originates from the s | Nov 27, 2025 | 9.9 | 33 | NO | NO |
CVE-2026-10106MEDIUM Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to verify that the channel referenced in an action cookie matches the channel of the target post, w | Jul 13, 2026 | 6.5 | 31 | NO | NO |
CVE-2026-9571MEDIUM Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to invalidate OAuth refresh tokens upon user account deactivation, which allows a deactivated user | Jul 13, 2026 | 6.5 | 31 | NO | NO |
CVE-2026-6347HIGH Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to sanitize sensitive configuration fields in the Mattermost Calls plugin which allows an attacker | May 18, 2026 | 7.6 | 31 | NO | NO |
Exploit Exposure
Signals from CVEs in this product scope (452 CVEs).
CISA KEV
0 CVEs
0.0% of CVEs· Bottom 1%
Metasploit
0 CVEs
0.0% of CVEs· Bottom 1%
Nuclei
0 CVEs
0.0% of CVEs· Bottom 1%
ExploitDB
0 CVEs
0.0% of CVEs· Bottom 1%
Social Chatter
Signals from CVEs in this product scope (452 CVEs).
Media Mentions
Signals from CVEs in this product scope (452 CVEs).
Top CNAs Publishing CVEs For Mattermost Server
Top CWEs
Versions
| Version | CVE Count | Avg CVSS | Avg EPSS | KEV | Exploits |
|---|---|---|---|---|---|
| 9.9.0 | 5 | 5.1 | 0.3% | 0 | 0 |
| 9.6.0 | 1 | 2.7 | 0.5% | 0 | 0 |
| 9.5.0 | 1 | 8.8 | 0.6% | 0 | 0 |
| 9.3.0 | 3 | 5.6 | 0.4% | 0 | 0 |
| 9.11.0 | 2 | 6.0 | 0.4% | 0 | 0 |
| 9.1.1 | 1 | 7.5 | 0.7% | 0 | 0 |
| 9.10.0 | 3 | 4.0 | 0.3% | 0 | 0 |
| 8.0.0 | 1 | 8.2 | 0.4% | 0 | 0 |
| 7.9.0 | 1 | 7.5 | 0.4% | 0 | 0 |
| 7.8.0 | 1 | 5.3 | 0.5% | 0 | 0 |
| 7.7.1 | 4 | 5.7 | 0.5% | 0 | 0 |
| 6.7.0 | 2 | 5.9 | 0.7% | 0 | 0 |
| 6.6.1 | 1 | 6.5 | 0.8% | 0 | 0 |
| 6.6.0 | 2 | 6.5 | 0.8% | 0 | 0 |
| 6.5.0 | 1 | 6.5 | 0.8% | 0 | 0 |
| 5.9.0 | 10 | 6.2 | 0.9% | 0 | 0 |
| 5.8.0 | 2 | 5.9 | 0.9% | 0 | 0 |
| 5.7.0 | 2 | 6.4 | 0.9% | 0 | 0 |
| 5.2.0 | 2 | 7.0 | 0.9% | 0 | 0 |
| 5.19.0 | 1 | 6.5 | 0.8% | 0 | 0 |