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    CVE-2026-3783

    When an OAuth2 bearer token is used for an HTTP(S) transfer, and that transfer performs a redirect to a second URL, curl could leak that token to the second hostname under some circumstances. If the hostname that the first request is redirected to has information in the used .netrc file, with either of the `machine` or `default` keywords, curl would pass on the bearer token set for the first host also to the second one.

    Published:Mar 11, 2026
    Last Modified:Mar 20, 2026
    EPS:Mar 11, 2026
    EPSS Score:0.00021
    CVSS Score:5.3

    Affected Products

    Vendor
    Curl
    Product
    Curl
    Vendor
    Haxx
    Product
    Curl

    Exploits

    https://hackerone.com/reports/3583983

    Common Attack Pattern Enumeration and Classification (CAPEC)

    CAPEC-102 Session Sidejacking
    CAPEC-12 Choosing Message Identifier
    CAPEC-217 Exploiting Incorrectly Configured SSL/TLS
    CAPEC-474 Signature Spoofing by Key Theft
    CAPEC-50 Password Recovery Exploitation
    CAPEC-509 Kerberoasting
    CAPEC-551 Modify Existing Service
    CAPEC-555 Remote Services with Stolen Credentials
    CAPEC-560 Use of Known Domain Credentials
    CAPEC-561 Windows Admin Shares with Stolen Credentials
    CAPEC-600 Credential Stuffing
    CAPEC-612 WiFi MAC Address Tracking
    CAPEC-613 WiFi SSID Tracking
    CAPEC-618 Cellular Broadcast Message Request
    CAPEC-619 Signal Strength Tracking
    CAPEC-621 Analysis of Packet Timing and Sizes
    CAPEC-622 Electromagnetic Side-Channel Attack
    CAPEC-623 Compromising Emanations Attack
    CAPEC-644 Use of Captured Hashes (Pass The Hash)
    CAPEC-645 Use of Captured Tickets (Pass The Ticket)
    CAPEC-652 Use of Known Kerberos Credentials
    CAPEC-653 Use of Known Operating System Credentials

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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