UBUNTU-CVE-2021-20177

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    UBUNTU-CVE-2021-20177

    Published: 12 Jan 2021Last Modified: 9 Sept 2026
    Upstream:
    CVE-2021-20177
    Aliases:
    USN-4750-1

    Summary:

    Details: A flaw was found in the Linux kernel's implementation of string matching within a packet. A privileged user (with root or CAP_NET_ADMIN) when inserting iptables rules could insert a rule which can panic the system. Kernel before kernel 5.5-rc1 is affected.

    References: https://ubuntu.com/security/CVE-2021-20177, https://bugzilla.kernel.org/show_bug.cgi?id=209823, https://ubuntu.com/security/notices/USN-4750-1, https://www.cve.org/CVERecord?id=CVE-2021-20177

    Affected packages

    Package

    Name: linux-hwe-edge

    Purl: pkg:deb/ubuntu/linux-hwe-edge?arch=source&distro=xenial

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -None

    Affected versions

    4.8.0-28.30~16.04.1
    4.8.0-30.32~16.04.1
    4.8.0-32.34~16.04.1
    4.8.0-34.36~16.04.1

    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
    UBUNTU-CVE-2021-20177 | CVE-DB