Log in Start free

Vulnerability · Published Oct 9, 2026 · Assigned by GitHub_M

CVE-2026-108261TinaCMS admin preview iframe loads an attacker-controlled origin from the URL fragment

Critical 9.3

In plain English

A critical-severity open redirect in app from @tinacms. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 9% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)9.3Critical
Exploit odds (30 days)0.2%top 90.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

Tina is a headless content management system. Prior to tinacms 3.14.0 and @tinacms/app 2.5.14, the /~/* admin preview route in packages/tinacms/src/admin/index.tsx can turn an attacker-controlled hash-router splat into an off-origin iframe URL through packages/@tinacms/app/src/preview.tsx, while packages/@tinacms/app/src/lib/preview-origin.ts derives expectedOrigin from that same URL for the GraphQL message channel in packages/@tinacms/app/src/lib/graphql-reducer.ts. An unauthenticated attacker can send a crafted link to a signed-in editor, cause the admin to frame an attacker origin, and have that frame treated as the trusted preview. The attacker-controlled frame can submit GraphQL reads or mutations that the admin executes with the editor credentials, exposing or modifying protected content. This issue is fixed in tinacms 3.14.0 and @tinacms/app 2.5.14.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
npm@tinacms/app2.5.14GHSA-x34j-47hf-4xg7
npmtinacms3.14.0GHSA-x34j-47hf-4xg7

Affected products (as reported)

VendorProductVersions
tinacms tinacms < 3.14.0
@tinacms app < 2.5.14

Weakness: CWE-346, CWE-441, CWE-601 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

References