Vulnerability · Published Sep 16, 2026 · Assigned by GitHub_M
CVE-2026-63506Tina: [Broken Access Control] letting any TinaCloud user authorize against any self-hosted site
High 8.8
In plain English
A high-severity authorization bypass via user-controlled key in auth from @tinacms. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 45% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Tina is a headless content management system. Prior to @tinacms/auth 1.1.4 and next-tinacms-azure 15.0.1, isAuthorized accepts a request-controlled clientID and asks isUserAuthorized to validate the bearer token against that selected TinaCloud app instead of the self-hosted site's configured app. An attacker with any TinaCloud account can submit the attacker's own app ID and valid token to a victim endpoint, causing TinaCloudBackendAuthProvider or an affected media authorized callback to accept the attacker's verified status across the tenant boundary. The vulnerable logic is present in packages/@tinacms/auth/src/index.ts and packages/next-tinacms-azure/src/auth.ts. Successful exploitation permits media listing, reading, upload, or deletion and, when TinaCloudBackendAuthProvider is used, GraphQL read, create, update, and delete operations on the victim's content without a victim account or victim interaction. This vulnerability is fixed in @tinacms/auth 1.1.4 and next-tinacms-azure 15.0.1.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | @tinacms/auth | 1.1.4 | GHSA-g74q-6g2f-874x |
| npm | next-tinacms-azure | 15.0.1 | GHSA-g74q-6g2f-874x |
Affected products (as reported)
Weakness: CWE-639 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
References
- https://github.com/tinacms/tinacms/security/advisories/GHSA-g74q-6g2f-874x x_refsource_CONFIRM
- https://github.com/tinacms/tinacms/pull/7168 x_refsource_MISC
- https://github.com/tinacms/tinacms/commit/0a927a4f8d228dd05ee7ca4be32899bc190e73af x_refsource_MISC
- https://github.com/tinacms/tinacms/releases/tag/@tinacms/auth@1.1.4 x_refsource_MISC
- https://github.com/tinacms/tinacms/releases/tag/next-tinacms-azure@15.0.1 x_refsource_MISC