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.
CVSS Details
- CVSS 3.1 Base Score: 6.5
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alma_linux | alma-upgrade-thunderbird | Jun 12, 2025 | May 14, 2025 | |
| Amazon Linux Ami 2 | amazon-linux-ami-2-upgrade-thunderbirdamazon-linux-ami-2-upgrade-thunderbird-debuginfo | May 30, 2025 | May 14, 2025 | |
| Debian | debian-upgrade-thunderbird | May 20, 2025 | May 14, 2025 | |
| Mozilla Thunderbird | mozilla-thunderbird-upgrade-138_0_1 | May 15, 2025 | May 13, 2025 | |
| Oracle_linux | — | oracle-linux-upgrade-thunderbird | May 29, 2025 | May 14, 2025 |
| Redhat_linux | redhat-upgrade-thunderbirdredhat-upgrade-thunderbird-debuginforedhat-upgrade-thunderbird-debugsource | May 29, 2025 | May 14, 2025 | |
| Rocky_linux | rocky-upgrade-thunderbirdrocky-upgrade-thunderbird-debuginforocky-upgrade-thunderbird-debugsource | Sep 9, 2025 | Jul 29, 2025 | |
| Suse | — | suse-upgrade-mozillathunderbirdsuse-upgrade-mozillathunderbird-translations-commonsuse-upgrade-mozillathunderbird-translations-other | May 26, 2025 | May 14, 2025 |
| Ubuntu | ubuntu-upgrade-thunderbird | Jul 23, 2025 | May 14, 2025 |
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