CVE-2026-84642
NONE—CVSS v3
—CVSS v2
—
EPSS (exploit probability)
—CWE
Description
The values of the mail.allowed_attachment_hostnames advanced config setting were used in a regular expression without escaping. For some possible valid hostnames, this could allow certain unintended hostnames to also match and serve remote attachments. This vulnerability was fixed in Thunderbird 155 and Thunderbird 153.2.
Affected routers (0)
No routers currently mapped to this CVE in our database.