vulnerability / NVI-00013967 / Revision 2
Tina: Cross-origin `POST /media/upload/*` requests can write arbitrary files into the Tina dev server media root
GitHub lists this reviewed advisory for @tinacms/cli. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
6.5 medium
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
0.264%
FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.18389. Missing scores are unknown.
As of · FIRST EPSS
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
@tinacms/cli
source listed< 2.5.2
### Summary A browser-based cross-origin request flaw in the Tina dev server allows an attacker-controlled website to cause arbitrary file creation inside the configured media upload directory on a developer machine running `tinacms dev`. No manual file upload is required. The attacker page builds the multipart request in JavaScript and sends it directly to the local Tina server. The browser blocks access to the response because of CORS, but the server still processes the request and writes the file. ### Details The issue is in the dev server path of `@tinacms/cli`. The Vite dev server installs CORS middleware: ```ts // packages/@tinacms/cli/src/next/vite/plugins.ts server.middlewares.use( cors({ origin: corsOriginCheck, methods: ['GET', 'HEAD', 'PUT', 'PATCH', 'POST', 'DELETE'], }) ); ``` For disallowed origins, the origin callback only returns `false` to the CORS library: ```ts // packages/@tinacms/cli/src/next/vite/cors.ts return (origin, callback) => { ... callback(null, false); }; ``` That does not reject the request server-side. The same request is still routed into the upload handler: ```ts // packages/@tinacms/cli/src/next/vite/plugins.ts if (req.url.
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. FIRST EPSS
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-rgr9-r7mj-mf6x ↗
GitHub Advisory Database · vendor advisory
Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.
- CVE-2026-63123 ↗
FIRST EPSS · official catalog
Observed . FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.
Public revision history
Only published revisions appear here. Routine fetches do not create a material-change event.
- Revision 2 ·
Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.
- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.