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    CVE-2026-2456

    Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 Mattermost fails to limit the size of responses from integration action endpoints, which allows an authenticated attacker to cause server memory exhaustion and denial of service via a malicious integration server that returns an arbitrarily large response when a user clicks an interactive message button.. Mattermost Advisory ID: MMSA-2026-00571

    Published:Mar 16, 2026
    Last Modified:Mar 30, 2026
    EPS:Mar 16, 2026
    EPSS Score:0.00036
    CVSS Score:5.3

    Affected Products

    Vendor
    Mattermost
    Product
    Mattermost
    Vendor
    Mattermost
    Product
    Mattermost Server
    Vendor
    Mattermost
    Product
    Server

    Exploits

    No exploit reference

    Common Attack Pattern Enumeration and Classification (CAPEC)

    No CAPEC recorded yet

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    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