CVE-2026-84992

md-editor-v3 is a Markdown editor for Vue 3 developed in JSX and TypeScript. Prior to 6.5.4, MdPreview's useMarkdownIt() highlight callback in packages/MdEditor/layouts/Content/composition/useMarkdownIt.ts inserts a fenced-code language value into class and language HTML attributes without escaping or consistently quoting it. Both highlighted and non-highlighted rendering paths reach this return value, while XSSPlugin filters only existing html_block and html_inline tokens before rendering and therefore cannot inspect the renderer-generated HTML. An attacker who can supply Markdown can use crafted fenced-code metadata to execute JavaScript in the application origin when a victim renders it, including as stored cross-site scripting when the host persists the Markdown. This issue is fixed in version 6.5.4

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/imzbf/md-editor-v3/commit/2c07360420e74087f5bc63032ab155d93e0a0b10
https://github.com/imzbf/md-editor-v3/releases/tag/v6.5.4
https://github.com/imzbf/md-editor-v3/security/advisories/GHSA-3rm2-h79c-8qw6
https://github.com/imzbf/md-editor-v3/security/advisories/GHSA-3rm2-h79c-8qw6

Configurations

No configuration.

History

18 Sep 2026, 18:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-18 18:17

Updated : 2026-09-24 21:25

NVD link : CVE-2026-84992

Mitre link : CVE-2026-84992

CVE.ORG link : CVE-2026-84992

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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