Medium severity · published Aug 17, 2026
CVE-2026-16046
Missing run-state validation on finished playbook runs
4.3
CVSS
0.3%
EPSS
No
On KEV
Description
Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to enforce run-state validation on write operations for finished playbook runs which allows a run participant to modify status, checklists, retrospective content, ownership, and participants on completed runs via REST and GraphQL API requests. Mattermost Advisory ID: MMSA-2026-00675
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 17% 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 11.7.6; 10.11.0 through 10.11.21 · source: vendor
MS
Mattermost Server · Mattermost
10.11.0 before 10.11.22; 11.7.0 before 11.7.7 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-16046
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-16046
Vendor Advisory
https://mattermost.com/security-updates
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