CVE-2026-90918 - Vulnerability Details - OpenCVE

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.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact Low

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Joomla! Project

Joomla! CMS

unaffected

Version	Status	Constraints
`4.0.0-5.4.8`	affected	—
`6.0.0-6.1.3`	affected	—

No data.

No data.

No data.

Project Subscriptions

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://developer.joomla.org/security-centre/1088-20260908-core-xss-in-html-mail-templates.html
https://www.joomla.org/

History

Tue, 29 Sep 2026 16:45:00 +0000

Type	Values Removed	Values Added
Description		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.
Title		Joomla! Core - [20260908] - Core - XSS in HTML Mail Templates in Joomla 4.0.0-5.4.8, 6.0.0-6.1.3
Weaknesses		CWE-79
References		https://developer.joomla.org/security-centre/1088-20260908-core-xss-in-html-mail-templates.html https://www.joomla.org/
Metrics		cvssV4_0 `{'score': 6.9, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: Joomla

Published: 2026-09-29T16:38:58.983Z

Updated: 2026-09-29T16:38:58.983Z

Reserved: 2026-09-14T11:03:59.813Z

Link: CVE-2026-90918

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-09-29T17:17:13.890

Modified: 2026-09-29T17:17:13.890

Link: CVE-2026-90918

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-79

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