Vulnerability Database

328,411

Total vulnerabilities in the database

Magento LTS vulnerable to Stored XSS via TinyMCE WYSIWYG Editor

From HackerOne report #1948040 by Halit AKAYDIN (hltakydn)

Impact

What kind of vulnerability is it? Who is impacted?

The TinyMCE WYSIWYG editor fails to filter scripts when rendering the HTML in specially crafted HTML tags.

Patches

Has the problem been patched? What versions should users upgrade to?

This vulnerability was fixed in version 20.2.0 by upgrading TinyMCE to a recent version in https://github.com/OpenMage/magento-lts/pull/3220

Workarounds

Is there a way for users to fix or remediate the vulnerability without upgrading?

The WYSIWYG editor features could be disabled in the configuration. Possibly some WAF appliances would filter this attack.

References

Are there any links users can visit to find out more?

The attack is simply an exploit of the "onmouseover" attribute of an img element as described on OWASP XSS Filter Evasion

CVSS v3:

  • Severity: Unknown
  • Score:
  • AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:L/A:L

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

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