Vulnerability Description
TinyMCE is an open source rich text editor. A mutation cross-site scripting (mXSS) vulnerability was discovered in TinyMCE’s core undo and redo functionality. When a carefully-crafted HTML snippet passes the XSS sanitisation layer, it is manipulated as a string by internal trimming functions before being stored in the undo stack. If the HTML snippet is restored from the undo stack, the combination of the string manipulation and reparative parsing by either the browser's native [DOMParser API](https://developer.mozilla.org/en-US/docs/Web/API/DOMParser) (TinyMCE 6) or the SaxParser API (TinyMCE 5) mutates the HTML maliciously, allowing an XSS payload to be executed. This vulnerability has been patched in TinyMCE 5.10.8 and TinyMCE 6.7.1 by ensuring HTML is trimmed using node-level manipulation instead of string manipulation. Users are advised to upgrade. There are no known workarounds for this vulnerability.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Tiny | Tinymce | < 5.10.8 |
Related Weaknesses (CWE)
References
- https://github.com/tinymce/tinymce/security/advisories/GHSA-v65r-p3vv-jjfvVendor Advisory
- https://researchgate.net/publication/266654651_mXSS_attacks_Attacking_well-securThird Party Advisory
- https://tiny.cloud/docs/release-notes/release-notes5108/#securityfixesRelease Notes
- https://tiny.cloud/docs/tinymce/6/6.7.1-release-notes/#security-fixesRelease Notes
- https://www.tiny.cloud/docs/api/tinymce.html/tinymce.html.saxparser/Product
- https://github.com/tinymce/tinymce/security/advisories/GHSA-v65r-p3vv-jjfvVendor Advisory
- https://researchgate.net/publication/266654651_mXSS_attacks_Attacking_well-securThird Party Advisory
- https://tiny.cloud/docs/release-notes/release-notes5108/#securityfixesRelease Notes
- https://tiny.cloud/docs/tinymce/6/6.7.1-release-notes/#security-fixesRelease Notes
- https://www.tiny.cloud/docs/api/tinymce.html/tinymce.html.saxparser/Product
FAQ
What is CVE-2023-45818?
CVE-2023-45818 is a vulnerability with a CVSS score of 6.1 (MEDIUM). TinyMCE is an open source rich text editor. A mutation cross-site scripting (mXSS) vulnerability was discovered in TinyMCE’s core undo and redo functionality. When a carefully-crafted HTML snippet pas...
How severe is CVE-2023-45818?
CVE-2023-45818 has been rated MEDIUM with a CVSS base score of 6.1/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2023-45818?
Check the references section above for vendor advisories and patch information. Affected products include: Tiny Tinymce.