CVE-2025-3523
6.4
MEDIUM
CVSS 3.1
EPSS 0.11%
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.
How to fix CVE-2025-3523
To remediate CVE-2025-3523, upgrade the affected package to a fixed version below.
- —upgrade to 1:128.10.1esr-1~deb11u1 or later
Is CVE-2025-3523 being exploited?
Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 1:128.10.1esr-1~deb11u1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM6.4 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:H/A:L |