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CVE-2026-47762 tinymce CVE debrief

TinyMCE, an open source rich text editor, contains a stored cross-site scripting (XSS) vulnerability in versions prior to 5.11.1, 7.9.3, and 8.5.1. The flaw exists in the handling of forged `mce:protected` HTML comments, which can be manipulated to bypass the editor's sanitization mechanisms. When content containing these malicious comments is later restored, embedded scripts execute in the victim's browser context. The vulnerability specifically affects deployments that utilize the `protect` configuration option. This is a HIGH severity issue with a CVSS 3.1 score of 8.7. The attack requires network access, low attack complexity, low privileges, and user interaction, with scope change and high impact to confidentiality and integrity. The vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation).

Vendor
tinymce
Product
Unknown
CVSS
HIGH 8.7
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-28
Original CVE updated
2026-05-28
Advisory published
2026-05-28
Advisory updated
2026-05-28

Who should care

Organizations using TinyMCE with the `protect` configuration option enabled, particularly those allowing user-generated content that persists and is later rendered to other users. Web application security teams, developers maintaining content management systems, and security operations centers monitoring for XSS exploitation in rich text editor components.

Technical summary

The vulnerability stems from improper handling of `mce:protected` HTML comments, a TinyMCE-specific mechanism intended to preserve certain content from editor processing. Attackers can forge these comments to smuggle malicious scripts past the editor's sanitization layer. When the protected content is subsequently restored or rendered, the embedded scripts execute. This represents a stored XSS vector where the payload persists in saved content and executes when viewed. The attack chain requires: (1) ability to inject content containing forged `mce:protected` comments, (2) the target instance to have the `protect` option enabled, and (3) victim interaction with restored content. The fix in versions 5.11.1, 7.9.3, and 8.5.1 addresses the parsing and validation of these protected comment structures.

Defensive priority

HIGH

Recommended defensive actions

  • Upgrade TinyMCE to version 5.11.1, 7.9.3, or 8.5.1 or later, depending on your major version branch.
  • If immediate patching is not possible, review and restrict use of the `protect` configuration option, as the vulnerability specifically impacts deployments utilizing this feature.
  • Implement Content Security Policy (CSP) headers as a defense-in-depth measure to mitigate impact of any successful XSS exploitation.
  • Audit stored content for presence of suspicious `mce:protected` comment patterns that may indicate prior exploitation attempts.
  • Review application logs for unusual content restoration events or unexpected script execution in TinyMCE editor contexts.

Evidence notes

CVE published and modified 2026-05-28 per NVD record. Vendor advisory and release notes confirm affected version ranges and fixes. CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N. CPE criteria confirm vulnerable versions: all versions below 5.11.1; 6.0.0 through 7.9.2; and 8.0.0 through 8.5.0.

Official resources

2026-05-28