UBUNTU-CVE-2021-33620

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    UBUNTU-CVE-2021-33620

    Published: 28 May 2021Last Modified: 4 Feb 2026
    Upstream:
    CVE-2021-33620
    Aliases:
    USN-4981-1

    Summary:

    Details: Squid before 4.15 and 5.x before 5.0.6 allows remote servers to cause a denial of service (affecting availability to all clients) via an HTTP response. The issue trigger is a header that can be expected to exist in HTTP traffic without any malicious intent by the server.

    References: https://ubuntu.com/security/CVE-2021-33620, https://github.com/squid-cache/squid/security/advisories/GHSA-572g-rvwr-6c7f, https://ubuntu.com/security/notices/USN-4981-1, https://www.cve.org/CVERecord?id=CVE-2021-33620

    Affected packages

    Package

    Name: squid3

    Purl: pkg:deb/ubuntu/[email protected]+esm6?arch=source&distro=esm-infra/xenial

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -None

    Affected versions

    3.3.8-1ubuntu16
    3.3.8-1ubuntu17

    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-2021-33620 | CVE-DB