TinyMCE Cross-Site Scripting (XSS) vulnerability using sanitization bypass through nested SVGs

published 2026-05-28 5 mo ago modified 2026-10-14 25 d ago also GHSA-mh5m-5hw4-5c69 , EUVD-2026-32920

cvss: 8.7; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 8%
public exploits: 0; none known

TinyMCE is an open source rich text editor. From 6.8.0 to before 7.1.0, TinyMCE contains an XSS vulnerability caused by improper SVG namespace scope handling in the sanitizer. A crafted payload using nested elements can bypass attribute sanitization and execute arbitrary JavaScript. This vulnerability is fixed in 7.1.0.

Patch / fix

fixed in 4

npm tinymce 7.1.0
nuget TinyMCE 7.1.0
packagist tinymce/tinymce 7.1.0
tiny tinymce 7.1.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-47760 updated 2026-06-28 cvss 5.4

TinyMCE: Cross-Site Scripting (XSS) vulnerability using sanitization bypass through nested SVGs

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 5 mo ago (2026-06-02)

Exploit prediction

0.19% chance of exploitation in the next 30 days, higher than 8% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.7	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
NVD	3.1	5.4	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
GitHub	3.1	8.7	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N

Affected packages

ecosystem	package	affected	fixed in
npm	tinymce	>=6.8.0, <7.1.0	7.1.0
nuget	TinyMCE	>=6.8.0, <7.1.0	7.1.0
packagist	tinymce/tinymce	>=6.8.0, <7.1.0	7.1.0

Affected products

tinymce tinymce

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

References

github.com /tinymce/tinymce/security/advisories/GHSA-mh5m-5hw4-5c69
web, vendor-advisory
nvd.nist.gov /vuln/detail/CVE-2026-47760
advisory
github.com /tinymce/tinymce
package

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary