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    CVE-2026-39834

    When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.

    Published:May 22, 2026
    Last Modified:May 28, 2026
    EPS:May 22, 2026
    EPSS Score:0.00055
    CVSS Score:9.1

    Affected Products

    Vendor
    Golang
    Product
    Crypto
    Vendor
    Golang
    Product
    Ssh

    Exploits

    No exploit reference

    Common Weakness Enumeration

    CWE-190 Integer Overflow or Wraparound

    Common Attack Pattern Enumeration and Classification (CAPEC)

    CAPEC-92 Forced Integer Overflow

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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