CVE-2024-29881 is a medium-severity (CVSS 4.3) Cross-site Scripting (XSS) vulnerability in tinymce. A fix is available for tinymce — see the affected versions and patch details below.
TinyMCE Cross-Site Scripting (XSS) vulnerability in handling external SVG files through Object or Embed elements
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-29881.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2024-29881 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
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 TinyMCE’s content loading and content inserting code. A SVG image could be loaded though an object or embed element and that image could potentially contain a XSS payload.
Fix
TinyMCE 6.8.1 introduced a new convert_unsafe_embeds option to automatically convert object and embed elements respective of their type attribute. From TinyMCE 7.0.0 onwards, the convert_unsafe_embeds option is enabled by default.
Workarounds
If you are using TinyMCE 6.8.1 or higher, set convert_unsafe_embeds to true. For any earlier versions, a custom NodeFilter is recommended to remove or modify any object or embed elements. This can be added using the editor.parser.addNodeFilter and editor.serializer.addNodeFilter APIs.
Acknowledgements
Tiny Technologies would like to thank Toni Huttunen of Fraktal Oy for discovering this vulnerability.
References
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | tinymce | all versions | 7.0.0npm install tinymce@7.0.0 |
| .NETNuGet | TinyMCE | all versions | 7.0.0dotnet add package TinyMCE --version 7.0.0 |
| 🐘Packagist | tinymce/tinymce | all versions | 7.0.0composer require tinymce/tinymce:^7.0.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for tinymce, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update tinymce to 7.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-29881 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2024-29881 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2024-29881. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2024-29881 in your dependencies?
O3 Security finds CVE-2024-29881 across npm, NuGet, Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.