LIVE · cybersecurity feed
Live wire
cve recordhigh

CVE-2026-84642

mozilla · thunderbird

Published
CVSS7.5
Severityhigh
WeaknessCWE-1333
ExploitedNot in CISA KEV

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

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.

References

← Back to the CVE Tracker

Our coverage of CVE-2026-84642

No stories yet. This page updates automatically when we publish reporting that references CVE-2026-84642.