Mattermost Agents 外掛漏洞 CVE-2026-93851 允許外掛替換與伺服器執行程式

Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10 fail to validate the target post ID in the Agents plugin's mention reminder component, which allows an authenticated user who can post in a channel visible to a system administrator to cause the administrator's browser to send an unintended API request, resulting in replacement of an installed plugin and code execution on the server, via a crafted post containing a forged mention reminder that the administrator clicks. Mattermost Advisory ID: MMSA-2026-00742

Impact

Affected Products

The following products are affected by CVE-2026-93851 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.

Update Mattermost to a patched version to fix a plugin vulnerability.

• Update Mattermost to version 11.9.2 or later.
• Update Mattermost to version 11.8.6 or later.
• Update Mattermost to version 11.7.11 or later.

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-93851.

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-93851 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-93851 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-93851 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-93851 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

• New CVE Received by [email protected]

  十月. 28, 2026

  Action	Type	Old Value	New Value
  Added	Description		Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10 fail to validate the target post ID in the Agents plugin's mention reminder component, which allows an authenticated user who can post in a channel visible to a system administrator to cause the administrator's browser to send an unintended API request, resulting in replacement of an installed plugin and code execution on the server, via a crafted post containing a forged mention reminder that the administrator clicks. Mattermost Advisory ID: MMSA-2026-00742
  Added	CVSS V3.1		AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H
  Added	CWE		CWE-22
  Added	Affected		New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/93xxx/CVE-2026-93851.json">CVE-2026-93851</a>
  Added	Reference		https://mattermost.com/security-updates

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.