cbcvebase.
CVE-2025-3523
published 2025-04-15

CVE-2025-3523: 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…

PriorityP431medium6.4CVSS 3.1
AVNACHPRNUIRSUCLIHAL
EPSS
0.30%
22.0th percentile
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.

Affected

8 ranges
VendorProductVersion rangeFixed in
debianthunderbird< thunderbird 1:128.10.0esr-1~deb12u1 (bookworm)thunderbird 1:128.10.0esr-1~deb12u1 (bookworm)
mozillafirefox
mozillathunderbird< 128.9.2128.9.2
mozillathunderbird>= 0 < 1:128.10.1esr-1~deb11u11:128.10.1esr-1~deb11u1
mozillathunderbird>= 0 < 1:128.10.0esr-1~deb12u11:128.10.0esr-1~deb12u1
mozillathunderbird>= 0 < 1:128.10.0esr-11:128.10.0esr-1
mozillathunderbird>= 0 < 1:128.10.0esr-11:128.10.0esr-1
mozillathunderbird>= 129.0 < 137.0.2137.0.2

CVSS provenance

nvdv3.16.4MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:H/A:L
osv6.4MEDIUM
vendor_debian6.4MEDIUM
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