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    CVE-2026-71920

    Multiple DrayTek VigorSwitch models contain a null pointer dereference vulnerability in the formlogout function. The vulnerability is caused by missing checks for an empty or absent Cookie header before string handling. A remote attacker can trigger this vulnerability via a crafted request to crash the service and cause a denial of service. Exploitation requires valid administrative credentials for the device's web management interface.

    Published:Aug 24, 2026
    Last Modified:Aug 24, 2026
    EPS:Aug 24, 2026
    EPSS Score:
    CVSS Score:4.9

    Affected Products

    Vendor
    Draytek
    Product
    Vigorswitch Fx2120 Firmware
    Vendor
    Draytek
    Product
    Vigorswitch G1282 Firmware
    Vendor
    Draytek
    Product
    Vigorswitch G2100 Firmware
    Vendor
    Draytek
    Product
    Vigorswitch G2121 Firmware
    Vendor
    Draytek
    Product
    Vigorswitch G2280x Firmware
    Vendor
    Draytek
    Product
    Vigorswitch G2540xs Firmware
    Vendor
    Draytek
    Product
    Vigorswitch P1282 Firmware
    Vendor
    Draytek
    Product
    Vigorswitch P2100 Firmware
    Vendor
    Draytek
    Product
    Vigorswitch P2280x Firmware
    Vendor
    Draytek
    Product
    Vigorswitch P2540xs Firmware
    Vendor
    Draytek
    Product
    Vigorswitch Pq2121x Firmware
    Vendor
    Draytek
    Product
    Vigorswitch Pq2200xb Firmware
    Vendor
    Draytek
    Product
    Vigorswitch Q2121x Firmware
    Vendor
    Draytek
    Product
    Vigorswitch Q2200x Firmware

    Exploits

    No exploit reference

    Common Weakness Enumeration

    CWE-476 NULL Pointer Dereference

    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