CVE Feed

    Dashboard / CVE / CVE-2026-93851

    CVE-2026-93851

    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

    Published:Oct 28, 2026
    Last Modified:Oct 29, 2026
    EPS:Oct 28, 2026
    EPSS Score:0.00266
    CVSS Score:8

    Affected Products

    Vendor
    Mattermost
    Product
    Mattermost

    Exploits

    No exploit reference

    Related CVEs

    CVE-2026-93846 (CVSS 3.8) — Mattermost versions 11.7.x <= 11.7.10 fail to restrict which built-in roles can be assigned to a team member v…
    CVE-2026-93848 (CVSS 2.7) — Mattermost versions 11.7.x <= 11.7.10 fail to apply outbound internal-connection filtering to the OpenID disco…
    CVE-2026-93850 (CVSS 6.5) — Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to bind the…
    CVE-2026-93849 (CVSS 6.5) — Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 Mattermost fail …
    CVE-2026-93847 (CVSS 3.5) — Mattermost versions 11.7.x <= 11.7.10 fail to validate reserved system post types on the scheduled post creati…
    CVE-2026-116516 (CVSS 6.5) — Mattermost versions <=11.9 11.1.9 11.5.8 11.10.7.0 fail to validate Zoom chat line length before slicing which…
    CVE-2026-13411 (CVSS 4.3) — Mattermost versions 11.7.x <= 11.7.11 fail to validate null elements when decoding playbook import conditions …
    CVE-2026-18799 (CVSS 4.3) — Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to restrict …
    CVE-2026-16251 (CVSS 6.5) — Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to limit the…
    CVE-2026-18256 (CVSS 4.3) — Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to properly …

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High