Description
It was possible to craft an email that showed a tracking link as an attachment. If the user attempted to open the attachment, Thunderbird automatically accessed the link. The configuration to block remote content did not prevent that. Thunderbird has been fixed to no longer allow access to web pages listed in the X-Mozilla-External-Attachment-URL header of an email. This vulnerability was fixed in Thunderbird 128.10.1 and Thunderbird 138.0.1.
References (4)
Scores
CVSS v3
6.5
EPSS
0.0028
EPSS Percentile
51.5%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-288
Status
published
Products (3)
mozilla/thunderbird
< 128.10.1
Mozilla/Thunderbird
128.10.1 - 128.*
Mozilla/Thunderbird
138.0.1
Published
May 14, 2025
Tracked Since
Feb 18, 2026