Special Element Injection in notebook

High10.0CVE-2021-32798 · Published Aug 23, 2021 · updated Sep 10, 2026

### Impact Untrusted notebook can execute code on load. This is a remote code execution, but requires user action to open a notebook. ### Patches 5.7.11, 6.4.1 ### References [OWASP Page on Injection Prevention](https://cheatsheetseries.owasp.org/cheatsheets/Injection_Prevention_Cheat_Sheet.html#injection-prevention-rules) ### For more information If you have any questions or comments about this advisory, or vulnerabilities to report, please email our security list security@ipython.org. Credit: Guillaume Jeanne from Google ### Example: A notebook with the following content in a cell and it would display an alert when opened for the first time in Notebook (in an untrusted state): ``` { "cell_type": "code", "execution_count": 0, "metadata": {}, "outputs": [ { "data": { "text/html": [ "<select><iframe></select><img src=x: onerror=alert('xss')>\n"], "text/plain": [] }, "metadata": {}, "output_type": "display_data" } ], "source": [ "" ] } ````