Low severity · published Oct 26, 2026
CVE-2026-93847
Improper post type validation on scheduled post endpoints
New
3.5
CVSS
0.2%
EPSS
No
On KEV
Description
Mattermost versions 11.7.x <= 11.7.10 fail to validate reserved system post types on the scheduled post creation and publication paths which allows an authenticated channel member to publish messages rendering as trusted system events via the scheduled post endpoint.. Mattermost Advisory ID: MMSA-2026-00732
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 7% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
11.7.0 through 11.7.10 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-93847
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-93847
mattermost.com
https://mattermost.com/security-updates
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