CVE-2026-90918: Joomla! Core - [20260908] - Core - XSS in HTML Mail Templates in Joomla 4.0.0-5.4.8, 6.0.0-6.1.3 - The mail template feature lacks an escaping mechanism…

PriorityP428medium5.3CVSS 3.1

AVNACLPRNUINSUCLINAN

EPSS

0.27%

17.3th percentile

Joomla! Core - [20260908] - Core - XSS in HTML Mail Templates in Joomla 4.0.0-5.4.8, 6.0.0-6.1.3 - The mail template feature lacks an escaping mechanism, causing XSS vectors in multiple extensions.

Affected

4 ranges

Vendor	Product	Version range	Fixed in
joomla!_project	joomla!_cms	—	—
joomla!_project	joomla!_cms	—	—
joomla	joomla_!	>= 4.0.0 < 5.4.8	5.4.8
joomla	joomla_!	>= 6.0.0 < 6.1.3	6.1.3

CVSS provenance

nvdv3.15.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

nvdv4.06.9MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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