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    CVE-2023-40703

    Mattermost fails to properly limit the characters allowed in different fields of a block in Mattermost Boards allowing a attacker to consume excessive resources, possibly leading to Denial of Service, by patching the field of a block using a specially crafted string. 

    Published:Nov 27, 2023
    Last Modified:Jun 3, 2025
    EPS:Nov 27, 2023
    EPSS Score:0.00091
    CVSS Score:4.3

    Affected Products

    Vendor
    Mattermost
    Product
    Mattermost

    Exploits

    No exploit reference

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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