CVE-2021-32798
CVSS v3
9.6
CRITICAL
EPSS Score
2.1 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
The Jupyter notebook is a web-based notebook environment for interactive computing. In affected versions untrusted notebook can execute code on load. Jupyter Notebook uses a deprecated version of Google Caja to sanitize user inputs. A public Caja bypass can be used to trigger an XSS when a victim opens a malicious ipynb document in Jupyter Notebook. The XSS allows an attacker to execute arbitrary code on the victim computer using Jupyter APIs.
Technical details
- Published
- 2021-08-09
Frequently asked questions
What is CVE-2021-32798?
The Jupyter notebook is a web-based notebook environment for interactive computing. In affected versions untrusted notebook can execute code on load. Jupyter Notebook uses a deprecated version of Google Caja to sanitize user inputs. A public Caja bypass can be used to trigger an XSS when a victim opens a malicious ipynb document in Jupyter Notebook. The XSS allows an attacker to execute arbitrary code on the victim computer using Jupyter APIs.
Is CVE-2021-32798 actively exploited?
Active exploitation of CVE-2021-32798 has not been confirmed. Its EPSS score was 2.1% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-32798?
CVE-2021-32798 has a CVSS v3 base score of 9.6 (CRITICAL severity).
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