CVE-2025-3909 (GCVE-0-2025-3909)
Vulnerability from cvelistv5
Published
2025-05-14 16:56
Modified
2025-05-16 03:55
Severity ?
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
CWE
  • JavaScript Execution via Spoofed PDF Attachment and file:/// Link
Summary
Thunderbird's handling of the X-Mozilla-External-Attachment-URL header can be exploited to execute JavaScript in the file:/// context. By crafting a nested email attachment (message/rfc822) and setting its content type to application/pdf, Thunderbird may incorrectly render it as HTML when opened, allowing the embedded JavaScript to run without requiring a file download. This behavior relies on Thunderbird auto-saving the attachment to /tmp and linking to it via the file:/// protocol, potentially enabling JavaScript execution as part of the HTML. This vulnerability affects Thunderbird < 128.10.1 and Thunderbird < 138.0.1.
References
Impacted products
Vendor Product Version
Mozilla Thunderbird Version: unspecified   < 128.10.1
 Create a notification for this product.
   Mozilla Thunderbird Version: unspecified   < 138.0.1
 Create a notification for this product.
Show details on NVD website

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