{"vulnerability": "CVE-2025-3909", "sightings": [{"uuid": "172b8350-c3e1-4562-ae27-9ec8379765bb", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "9f56dd64-161d-43a6-b9c3-555944290a09", "vulnerability": "CVE-2025-3909", "type": "seen", "source": "https://t.me/DarkWebInformer_CVEAlerts/16350", "content": "\ud83d\udd17 DarkWebInformer.com - Cyber Threat Intelligence\n\ud83d\udccc CVE ID: CVE-2025-3909\n\ud83d\udd25 CVSS Score: N/A\n\ud83d\udd39 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 < 128.10.1 and Thunderbird < 138.0.1.\n\ud83d\udccf Published: 2025-05-14T16:56:43.630Z\n\ud83d\udccf Modified: 2025-05-14T16:56:43.630Z\n\ud83d\udd17 References:\n1. https://bugzilla.mozilla.org/show_bug.cgi?id=1958376\n2. https://www.mozilla.org/security/advisories/mfsa2025-34/\n3. https://www.mozilla.org/security/advisories/mfsa2025-35/", "creation_timestamp": "2025-05-14T17:32:22.000000Z"}]}