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    CVE-2021-43980

    The simplified implementation of blocking reads and writes introduced in Tomcat 10 and back-ported to Tomcat 9.0.47 onwards exposed a long standing (but extremely hard to trigger) concurrency bug in Apache Tomcat 10.1.0 to 10.1.0-M12, 10.0.0-M1 to 10.0.18, 9.0.0-M1 to 9.0.60 and 8.5.0 to 8.5.77 that could cause client connections to share an Http11Processor instance resulting in responses, or part responses, to be received by the wrong client.

    Published:Sep 28, 2022
    Last Modified:May 21, 2025
    EPS:Sep 28, 2022
    EPSS Score:0.00162
    CVSS Score:3.7

    Affected Products

    Vendor
    Apache
    Product
    Tomcat
    Vendor
    Debian
    Product
    Debian Linux
    Vendor
    Redhat
    Product
    Jboss Enterprise Web Server

    Exploits

    No exploit reference

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    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