UBUNTU-CVE-2021-36740

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    UBUNTU-CVE-2021-36740

    Published: 14 Jul 2021Last Modified: 22 Apr 2026
    Upstream:
    CVE-2021-36740
    Aliases:
    USN-5474-1

    Summary:

    Details: Varnish Cache, with HTTP/2 enabled, allows request smuggling and VCL authorization bypass via a large Content-Length header for a POST request. This affects Varnish Enterprise 6.0.x before 6.0.8r3, and Varnish Cache 5.x and 6.x before 6.5.2, 6.6.x before 6.6.1, and 6.0 LTS before 6.0.8.

    References: https://ubuntu.com/security/CVE-2021-36740, https://varnish-cache.org/security/VSV00007.html, https://github.com/varnishcache/varnish-cache/commit/9be22198e258d0e7a5c41f4291792214a29405cf, https://github.com/varnishcache/varnish-cache/commit/82b0a629f60136e76112c6f2c6372cce77b683be, https://github.com/varnishcache/varnish-cache/commit/82b0a629f60136e76112c6f2c6372cce77b683be, https://github.com/varnishcache/varnish-cache/commit/9be22198e258d0e7a5c41f4291792214a29405cf, https://docs.varnish-software.com/security/VSV00007/, https://ubuntu.com/security/notices/USN-5474-1, https://www.cve.org/CVERecord?id=CVE-2021-36740

    Affected packages

    Package

    Name: varnish

    Purl: pkg:deb/ubuntu/[email protected]?arch=source&distro=focal

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -6.2.1-2ubuntu0.1

    Affected versions

    6.1.1-1

    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-2021-36740 | CVE-DB