CVE-2026-55661

Tina is a headless content management system. In versions prior to @tinacms/mdx 2.1.7 and tinacms 3.9.3, rich-text parsing and the default link/image renderers did not sanitize the url field on Slate link/image nodes. Content containing javascript: or data:text/html URLs — including case-variant, whitespace-padded, and control-character-obfuscated forms — is rendered into href/src and executes when the content is viewed. Any actor able to author rich-text content (for example a lower-privileged editor, or imported/external content) can achieve stored XSS against editors and site viewers. This issue is fixed in versions @tinacms/mdx 2.1.7 and tinacms 3.9.3.

CVSS

No CVSS.

References

Link	Resource
https://github.com/tinacms/tinacms/pull/7056
https://github.com/tinacms/tinacms/security/advisories/GHSA-2vcc-5v34-9jc8

Configurations

No configuration.

History

01 Jul 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-01 21:17

Updated : 2026-07-06 16:16

NVD link : CVE-2026-55661

Mitre link : CVE-2026-55661

CVE.ORG link : CVE-2026-55661

JSON object : View

Products Affected

No product.

CWE

CWE-79

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

CWE-87

Improper Neutralization of Alternate XSS Syntax

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