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    CVE-2026-19401

    Any remote client can crash a (debugging/non-release build type) NSD serve child by sending it a special crafted message with a specially tuned number of DNS Cookie options (17 when UDP payload size is 512). By continuously crashing the serve childs, the remote client can severely hamper or, when positioned sufficiently close, deny all DNS service.

    Published:Aug 26, 2026
    Last Modified:Sep 1, 2026
    EPS:Aug 26, 2026
    EPSS Score:0.00332
    CVSS Score:8.2

    Affected Products

    Vendor
    Nlnetlabs
    Product
    Nsd

    Exploits

    No exploit reference

    Related CVEs

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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