EUVD-2026-385235

fkie_cve-2026-108260

Tina is a headless content management system. Prior to 0.2.1, the tina-markdown element in packages/@tinacms/web-components/src/tina-markdown.js assigns a rich-text node.url value directly to an anchor href without validating the URL scheme. A content author can store a link using a script-capable scheme, and a visitor who clicks the rendered link executes attacker-controlled script in the site's origin. The script can access same-origin application data and, when the visitor is an editor or administrator, may expose credentials stored by the TinaCMS admin on that origin. This issue is fixed in version 0.2.1.

GHSA-c42q-qvc3-j6vg — @tinacms/web-components: `tina-markdown` writes rich-text link URLs into `href` without scheme validation, allowing sto…

Affected: npm: @tinacms/web-components

### Summary

`<tina-markdown>` renders a rich-text AST into the DOM and, for `a` nodes, assigns the node's URL straight to the anchor's `href` with no scheme check. A link authored in the CMS as `javascript:…` renders as a live `javascript:` anchor, so a visitor who clicks it executes attacker-supplied script in the site's origin. Every sibling renderer in the repository already sanitizes these URLs; this one does not.

### Details

The unvalidated sink:

``` packages/@tinacms/web-components/src/tina-markdown.js:67-69 if (node.type === 'html' || node.type === 'html_inline') { return DOMPurify.sanitize(node.value, { RETURN_DOM_FRAGMENT: true }); } packages/@tinacms/web-components/src/tina-markdown.js:75 if (node.url && node.type === 'a') el.href = node.url; packages/@tinacms/web-components/src/tina-markdown.js:76 if (node.url && node.type === 'img') el.src = node.url; ```

`node.url` comes from the `content` attribute the site populates from the TinaCMS content API (`:169-176`), i.e. whatever a content author typed into a rich-text field. The DOMPurify call at `:68` handles only raw-HTML node values and returns before the anchor branch, so it never inspects `node.url`. Line 75 is a direct property assignment — no HTML parser, no sanitizer. The `mode: 'open'` shadow root (`:164-167`) provides no script isolation.

The guard that exists in every sibling renderer:

``` packages/@tinacms/mdx/src/sanitize-url.ts:10 allowedSchemes = ['http','https','mailto','…

Most recent entries from all

EUVD-2026-385235

fkie_cve-2026-108260

GHSA-c42q-qvc3-j6vg — @tinacms/web-components: `tina-markdown` writes rich-text link URLs into `href` without scheme validation, allowing sto…