GHSA-5vm8-hhgr-jcjp
GHSA-5vm8-hhgr-jcjp is a security vulnerability in tinymce. O3 Security confirms whether GHSA-5vm8-hhgr-jcjp is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Cross-site scripting vulnerability in TinyMCE
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
tinymcenpmDescription
Impact
A cross-site scripting (XSS) vulnerability was discovered in the URL sanitization logic of the core parser for form elements. The vulnerability allowed arbitrary JavaScript execution when inserting a specially crafted piece of content into the editor using the clipboard or APIs, and then submitting the form. However, as TinyMCE does not allow forms to be submitted while editing, the vulnerability could only be triggered when the content was previewed or rendered outside of the editor. This impacts all users who are using TinyMCE 5.7.0 or lower.
Patches
This vulnerability has been patched in TinyMCE 5.7.1 by improved URL sanitization logic.
Workarounds
To work around this vulnerability, either:
- Upgrade to TinyMCE 5.7.1 or higher
- Manually sanitize
formURL attributes using a TinyMCE node filter. - Disable
formelements in your content using the invalid_elements setting.
Example: Sanitizing using a node filter
editor.parser.addNodeFilter('form', 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);
});
}
});
});
Example: Using invalid_elements
invalid_elements: 'form'
Acknowledgements
Tiny Technologies would like to thank Mikhail Khramenkov at Solar Security Research Team for discovering this vulnerability.
References
https://www.tiny.cloud/docs/release-notes/release-notes571/#securityfixes
For more information
If you have any questions or comments about this advisory:
- Open an issue in the TinyMCE repo
- Email us at [email protected]
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | tinymce | all versions | 5.7.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for tinymce. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update tinymce to 5.7.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-5vm8-hhgr-jcjp is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-5vm8-hhgr-jcjp is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-5vm8-hhgr-jcjp. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-5vm8-hhgr-jcjp in your dependencies?
O3 detects GHSA-5vm8-hhgr-jcjp across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.