CVE-2021-32798

mediumpriority · track · 39EPSS 0.021 · 82 %ileEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
2.11% (82nd) EPSS
CVSS 6.8 · medium
Is it mine?
16 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · osv

EPSS · scored 2026-10-27

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

10.0
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–critical · 6.8–10

v2.06.8mediumAV:N/AC:M/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 8.6 · impact 6.4
v3.19.6criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 6
v3.19.6criticalAV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU
v3.110criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Nsecondary · ENISA EU
v3.110criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Nsecondary · security-advisories@github.comexploitability 3.9 · impact 5.8
v3.110criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Nsecondary · OSV
v3.18.8highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)
02

weaknesses

The CWE weakness classes this flaw belongs to.

03

affected products (16)

Products and version ranges known to be affected.

04

advisories (4)

Vendor and ecosystem advisories describing this.

  • GHSA-hwvq-6gjx-j797Special Element Injection in notebook2021-08-23ghsa · osvUS

    ### 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": [ "" ] } ````

  • BIT-jupyter-base-notebook-2021-32798Failure to Sanitize Special Elements into a Different Plane (Special Element Injection) in notebook2024-03-06vendor · osvUS

    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.

  • BIT-jupyter-notebook-2021-32798Failure to Sanitize Special Elements into a Different Plane (Special Element Injection) in notebook2024-03-06vendor · osvUS

    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.

  • PYSEC-2021-1182021-08-09vendor · osvUS

    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.

05

also known as (9)

Other names and identifiers for this entity.

06

sources

Which sources assert this record, and when.

published 2021-08-09modified 2026-06-17
08

references (7)

External citations — patches, advisories, analysis.

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