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    CVE-2021-36740

    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.

    Published:Jul 13, 2021
    Last Modified:Nov 21, 2024
    EPS:Jul 14, 2021
    EPSS Score:0.00122
    CVSS Score:6.5

    Affected Products

    Vendor
    Debian
    Product
    Debian Linux
    Vendor
    Fedoraproject
    Product
    Fedora
    Vendor
    Redhat
    Product
    Enterprise Linux
    Vendor
    Redhat
    Product
    Rhel Eus
    Vendor
    Redhat
    Product
    Rhel Software Collections
    Vendor
    Varnish-cache
    Product
    Varnish Cache
    Vendor
    Varnish-software
    Product
    Varnish Cache
    Vendor
    Varnish Cache Project
    Product
    Varnish Cache

    Exploits

    No exploit reference

    Common Attack Pattern Enumeration and Classification (CAPEC)

    CAPEC-273 HTTP Response Smuggling
    CAPEC-33 HTTP Request Smuggling

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    References

    https://docs.varnish-software.com/security/VSV00007/
    https://github.com/varnishcache/varnish-cache/commit/82b0a629f60136e76112c6f2c6372cce77b683be
    https://github.com/varnishcache/varnish-cache/commit/9be22198e258d0e7a5c41f4291792214a29405cf
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/THV2DQA2GS65HUCKK4KSD2XLN3AAQ2V5/
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZHBNLDEOTGYRIEQZBWV7F6VPYS4O2AAK/
    https://varnish-cache.org/security/VSV00007.html
    https://www.debian.org/security/2022/dsa-5088
    https://docs.varnish-software.com/security/VSV00007/
    https://github.com/varnishcache/varnish-cache/commit/82b0a629f60136e76112c6f2c6372cce77b683be
    https://github.com/varnishcache/varnish-cache/commit/9be22198e258d0e7a5c41f4291792214a29405cf
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/THV2DQA2GS65HUCKK4KSD2XLN3AAQ2V5/
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZHBNLDEOTGYRIEQZBWV7F6VPYS4O2AAK/
    https://varnish-cache.org/security/VSV00007.html
    https://www.debian.org/security/2022/dsa-5088

    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