CVE-2026-55660

Tina is a headless content management system. In versions prior to @tinacms/app 2.5.6 and tinacms 3.9.3, cross-origin postMessage handlers and a rich-text URL-sanitization bypass enable stored XSS and session takeover. The library registers window message listeners — the useTina overlay handler, the OAuth authentication popup handler, and the admin↔preview iframe GraphQL reducer — that act on event.data without verifying event.origin or event.source and post messages using non-specific target origins, while insufficient URL sanitization in rich-text content allows malicious URLs to persist and execute. A page the victim visits (or a window in an opener/iframe relationship with a Tina admin) can forge messages to drive the editor, inject preview content, or observe/forge the OAuth popup channel to take over an authenticated editing session. This issue has been fixed in versions @tinacms/app 2.5.6 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-g5qx-h5f3-mp2f

Configurations

No configuration.

History

01 Jul 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-01 21:17

Updated : 2026-07-02 17:45

NVD link : CVE-2026-55660

Mitre link : CVE-2026-55660

CVE.ORG link : CVE-2026-55660

JSON object : View

Products Affected

No product.

CWE

CWE-79

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

CWE-346

Origin Validation Error

CWE-601

URL Redirection to Untrusted Site ('Open Redirect')

CWE-940

Improper Verification of Source of a Communication Channel

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