6.1 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality Impact
LOW
Integrity Impact
LOW
Availability Impact
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
0.004 Low
EPSS
Percentile
73.3%
A cross-site scripting (XSS) vulnerability was discovered in the URL sanitization logic of the core parser. The vulnerability allowed arbitrary JavaScript execution when inserting a specially crafted piece of content into the editor using the clipboard or APIs. This impacts all users who are using TinyMCE 5.5.1 or lower.
This vulnerability has been patched in TinyMCE 5.6.0 by improved URL sanitization logic.
To work around this vulnerability, either:
iframe
, object
and embed
URL attributes using a TinyMCE node filter.iframe
, object
, and embed
elements in your content using the invalid_elements setting.editor.parser.addNodeFilter('iframe,object,embed', function(nodes) {
nodes.forEach(function(node) {
if (node.attributes) {
node.attributes.forEach(function(attr) {
var name = attr.name;
var value = attr.value;
// Sanitize the attribute value here or remove it entirely
var sanitizedValue = ...;
node.attr(name, santizedValue);
});
}
});
});
invalid_elements: 'iframe,object,embed'
Tiny Technologies would like to thank Aaron Bishop at SecurityMetrics for discovering this vulnerability.
https://www.tiny.cloud/docs/release-notes/release-notes56/#securityfixes
If you have any questions or comments about this advisory: