vulnerability
Red Hat: CVE-2025-3909: thunderbird: JavaScript Execution via Spoofed PDF Attachment and file:/// Link (Multiple Advisories)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 6 | (AV:N/AC:L/Au:N/C:P/I:P/A:N) | May 14, 2025 | May 29, 2025 | Jun 11, 2025 |
Severity
6
CVSS
(AV:N/AC:L/Au:N/C:P/I:P/A:N)
Published
May 14, 2025
Added
May 29, 2025
Modified
Jun 11, 2025
Description
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
Solution(s)
redhat-upgrade-thunderbirdredhat-upgrade-thunderbird-debuginforedhat-upgrade-thunderbird-debugsource
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