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    CVE-2021-40346

    An integer overflow exists in HAProxy 2.0 through 2.5 in htx_add_header that can be exploited to perform an HTTP request smuggling attack, allowing an attacker to bypass all configured http-request HAProxy ACLs and possibly other ACLs.

    Published:Sep 8, 2021
    Last Modified:Nov 21, 2024
    EPS:Sep 8, 2021
    EPSS Score:0.92742
    CVSS Score:7.5

    Affected Products

    Vendor
    Debian
    Product
    Debian Linux
    Vendor
    Fedoraproject
    Product
    Fedora
    Vendor
    Haproxy
    Product
    Haproxy
    Vendor
    Redhat
    Product
    Openshift

    Exploits

    https://jfrog.com/blog/critical-vulnerability-in-haproxy-cve-2021-40346-integer-overflow-enables-http-smuggling/https://jfrog.com/blog/critical-vulnerability-in-haproxy-cve-2021-40346-integer-overflow-enables-http-smuggling/https://github.com/alexOarga/CVE-2021-40346https://github.com/alikarimi999/CVE-2021-40346https://github.com/BoianEduard/CVE-2021-40346https://github.com/donky16/CVE-2021-40346-POChttps://github.com/jmg0929/CVE-2021-40346https://github.com/knqyf263/CVE-2021-40346https://github.com/Vulnmachines/HAProxy_CVE-2021-40346

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    References

    https://git.haproxy.org/?p=haproxy.git
    https://github.com/haproxy/haproxy/commit/3b69886f7dcc3cfb3d166309018e6cfec9ce2c95
    https://jfrog.com/blog/critical-vulnerability-in-haproxy-cve-2021-40346-integer-overflow-enables-http-smuggling/
    https://lists.apache.org/thread.html/r284567dd7523f5823e2ce995f787ccd37b1cc4108779c50a97c79120%40%3Cdev.cloudstack.apache.org%3E
    https://lists.apache.org/thread.html/r8a58fd7a29808e5d27ee56877745e58dc4bb041b9af94601554e2a5a%40%3Cdev.cloudstack.apache.org%3E
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/A7V2IYO22LWVBGUNZWVKNTMDV4KINLFO/
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MXTSBY2TEAXWZVFQM3CXHJFRONX7PEMN/
    https://www.debian.org/security/2021/dsa-4968
    https://www.mail-archive.com/haproxy%40formilux.org
    https://www.mail-archive.com/haproxy%40formilux.org/msg41114.html
    https://git.haproxy.org/?p=haproxy.git
    https://github.com/haproxy/haproxy/commit/3b69886f7dcc3cfb3d166309018e6cfec9ce2c95
    https://jfrog.com/blog/critical-vulnerability-in-haproxy-cve-2021-40346-integer-overflow-enables-http-smuggling/
    https://lists.apache.org/thread.html/r284567dd7523f5823e2ce995f787ccd37b1cc4108779c50a97c79120%40%3Cdev.cloudstack.apache.org%3E
    https://lists.apache.org/thread.html/r8a58fd7a29808e5d27ee56877745e58dc4bb041b9af94601554e2a5a%40%3Cdev.cloudstack.apache.org%3E
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/A7V2IYO22LWVBGUNZWVKNTMDV4KINLFO/
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MXTSBY2TEAXWZVFQM3CXHJFRONX7PEMN/
    https://www.debian.org/security/2021/dsa-4968
    https://www.mail-archive.com/haproxy%40formilux.org
    https://www.mail-archive.com/haproxy%40formilux.org/msg41114.html

    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