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    CVE-2026-4873

    A vulnerability exists where a connection requiring TLS incorrectly reuses an existing unencrypted connection from the same connection pool. If an initial transfer is made in clear-text (via IMAP, SMTP, or POP3), a subsequent request to that same host bypasses the TLS requirement and instead transmit data unencrypted.

    Published:Apr 29, 2026
    Last Modified:May 14, 2026
    EPS:May 13, 2026
    EPSS Score:0.00021
    CVSS Score:5.9

    Affected Products

    Vendor
    Curl
    Product
    Curl
    Vendor
    Haxx
    Product
    Curl

    Exploits

    https://hackerone.com/reports/3621851

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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