UBUNTU-CVE-2018-20021

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    UBUNTU-CVE-2018-20021

    Published: 19 Dec 2018Last Modified: 20 May 2026
    Upstream:
    CVE-2018-20021
    Aliases:
    USN-3877-1
    USN-4547-1
    USN-4547-2

    Summary:

    Details: LibVNC before commit c3115350eb8bb635d0fdb4dbbb0d0541f38ed19c contains a CWE-835: Infinite loop vulnerability in VNC client code. Vulnerability allows attacker to consume excessive amount of resources like CPU and RAM

    References: https://ubuntu.com/security/CVE-2018-20021, https://ics-cert.kaspersky.com/advisories/klcert-advisories/2018/12/19/klcert-18-031-libvnc-infinite-loop/, https://ubuntu.com/security/notices/USN-3877-1, https://ubuntu.com/security/notices/USN-4547-1, https://ubuntu.com/security/notices/USN-4547-2, https://ubuntu.com/security/notices/USN-4587-1, https://www.cve.org/CVERecord?id=CVE-2018-20021

    Affected packages

    Package

    Name: libvncserver

    Purl: pkg:deb/ubuntu/libvncserver?arch=source&distro=trusty

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -0.9.9+dfsg-1ubuntu1.4

    Affected versions

    0.9.9+dfsg-1
    0.9.9+dfsg-1ubuntu1
    0.9.9+dfsg-1ubuntu1.1
    0.9.9+dfsg-1ubuntu1.2
    0.9.9+dfsg-1ubuntu1.3

    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