VULNERABILITY INTELLIGENCE

CVE-2025-3523

CVSS score6.4 MEDIUM
EPSS probability0.32%
CISA KEVNot currently listed
Published2025-04-15
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:H/A:L

Description

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.

Weakness classification

  • 134c704f-9b21-4f2e-91b3-4a467353bcc0: CWE-451

Primary references