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    CVE-2025-3523

    When an email contains multiple attachments with external links via the X-Mozilla-External-Attachment-URL header, only the last link is shown when hovering over any attachment. Although the correct link is used on click, the misleading hover text could trick users into downloading content from untrusted sources. This vulnerability was fixed in Thunderbird 137.0.2 and Thunderbird 128.9.2.

    Published:Apr 15, 2025
    Last Modified:Apr 20, 2026
    EPS:Apr 15, 2025
    EPSS Score:0.00244
    CVSS Score:6.4

    Affected Products

    Vendor
    Mozilla
    Product
    Thunderbird
    Vendor
    Redhat
    Product
    Enterprise Linux
    Vendor
    Redhat
    Product
    Rhel Aus
    Vendor
    Redhat
    Product
    Rhel E4s
    Vendor
    Redhat
    Product
    Rhel Eus
    Vendor
    Redhat
    Product
    Rhel Tus

    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