UBUNTU-CVE-2021-20257

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    UBUNTU-CVE-2021-20257

    Published: 23 Feb 2021Last Modified: 9 Jun 2026
    Upstream:
    CVE-2021-20257

    Summary:

    Details: An infinite loop flaw was found in the e1000 NIC emulator of the QEMU. This issue occurs while processing transmits (tx) descriptors in process_tx_desc if various descriptor fields are initialized with invalid values. This flaw allows a guest to consume CPU cycles on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.

    References: https://ubuntu.com/security/CVE-2021-20257, https://lists.gnu.org/archive/html/qemu-devel/2021-02/msg03595.html, https://www.openwall.com/lists/oss-security/2021/02/25/2, https://ubuntu.com/security/notices/USN-5010-1, https://www.cve.org/CVERecord?id=CVE-2021-20257, https://ubuntu.com/security/notices/USN-8412-1

    Affected packages

    Package

    Name: qemu

    Purl: pkg:deb/ubuntu/qemu?arch=source&distro=esm-infra-legacy%2Ftrusty

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -2.0.0+dfsg-2ubuntu1.47+esm6

    Affected versions

    1.5.0+dfsg-3ubuntu5
    1.5.0+dfsg-3ubuntu6

    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
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