Medium severity · published Mar 16, 2026
CVE-2026-2462
Admin RCE via Malicious Plugin Upload on CI Test Instances
6.6
CVSS
0.3%
EPSS
No
On KEV
Description
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to restrict plugin installation on CI test instances with default admin credentials which allows an unauthenticated attacker to achieve remote code execution and exfiltrate sensitive configuration data including AWS and SMTP credentials via uploading a malicious plugin after changing the import directory. Mattermost Advisory ID: MMSA-2025-00528
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:L
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
Low
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 27% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
11.3.0 through 11.3.0; 11.2.0 through 11.2.2; 10.11.0 through 10.11.10 · source: vendor
MS
Mattermost Server · Mattermost
10.11.0 before 10.11.11; 11.2.0 before 11.2.3; 11.3.0 before 11.3.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-2462
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-2462
Vendor Advisory
https://mattermost.com/security-updates
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