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.
Scores
CVSS v3
6.4
EPSS
0.0024
EPSS Percentile
47.6%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:H/A:L
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-451
Status
published
Products (3)
mozilla/thunderbird
< 128.9.2
Mozilla/Thunderbird
128.9.2 - 128.*
Mozilla/Thunderbird
137.0.2
Published
Apr 15, 2025
Tracked Since
Feb 18, 2026