CVE-2026-2462
Unauthorized Plugin Installation in Mattermost Enables Remote Code Execution
Publication date: 2026-03-16
Last updated on: 2026-03-18
Assigner: Mattermost, Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| mattermost | mattermost_server | From 10.11.0 (inc) to 10.11.11 (exc) |
| mattermost | mattermost_server | From 11.2.0 (inc) to 11.2.3 (exc) |
| mattermost | mattermost_server | From 11.3.0 (inc) to 11.3.1 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-863 | The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability affects certain versions of Mattermost (11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10) where the system fails to restrict plugin installation on continuous integration (CI) test instances that use default admin credentials.
An unauthenticated attacker can exploit this by uploading a malicious plugin after changing the import directory, which allows them to execute remote code and exfiltrate sensitive configuration data such as AWS and SMTP credentials.
How can this vulnerability impact me? :
The vulnerability can lead to remote code execution by an unauthenticated attacker, which means the attacker can run arbitrary code on the affected system.
Additionally, sensitive configuration data including AWS and SMTP credentials can be stolen, potentially leading to further compromise of cloud resources, email systems, and other integrated services.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, you should avoid using default admin credentials on CI test instances of Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, and 10.11.x <= 10.11.10.
Additionally, restrict plugin installation permissions to trusted users only and ensure that the import directory cannot be changed by unauthorized users.
Consider upgrading to a fixed version of Mattermost once available or applying any official patches provided by Mattermost as per their advisory MMSA-2025-00528.