CVE-2026-44727
CriticalAdvisory
Published 18 Jun 2026In the index since 6 Sept 2026
- Severity
- Critical
- worst across findings
- CVSS
- 9.3
- base score, highest
- EPSS
- 0.004
- 37th percentile
- CISA KEV
- Not listed
- no confirmed exploitation
- Charts affected
- 6
- of 17,781 indexed, latest versions
- Container images
- 6
- deployed by those charts
- Fix available
- 1 of 1
- affected package
Jupyter Server: Stored XSS in `NbconvertFileHandler` / `NbconvertPostHandler` via missing `sandbox` CSP
Carried by container images the latest versions of 6 of 17,781 indexed charts deploy, on 6 images.
| Affected package | Affected versions | Fixed in | Images |
|---|---|---|---|
| jupyter-serverpypi | 2.0.4, 2.7.0, 2.12.4, 2.14.2+1 more | 2.20.0 | 6 |
- OSV records
- PYSEC-2026-366
- Also known as
- GHSA-fcw5-x6j4-ccmp
Charts affected
6 by stars
| Chart | Latest | Affected images | Radar Score |
|---|---|---|---|
| daskdask | 2024.1.1 | 1 of 2See more | 12,746 |
| daskhubdask | 2024.1.1 | 1 of 9See more | 14,094 |
| jupyterhub-outpostjupyter-jscVerified publisher | 2.4.1 | 1 of 1See more | 1,678 |
| jupyterhubd4nVerified publisher | 3.3.7 | 1 of 7See more | 16,604 |
| jupyterhubkubeblocksVerified publisher | 0.1.0 | 1 of 7See more | 7,356 |
| kyso-nbdimekyso | 1.0.0 | 1 of 1See more | 2,765 |
Container images carrying it
6 by charts deploying them
A fixed version is listed for 1 of the 1 affected package.
| Container image | Digest | Package | Fixed in | Used by |
|---|---|---|---|---|
| aristidetm/ | 469dbc951224 | jupyter-server | 2.20.0 | 1 |
| jupyterhub/ | 8e4778efec8e | jupyter-server | 2.20.0 | 1 |
| jupyterjsc/ | aea53b13f235 | jupyter-server | 2.20.0 | 1 |
| kyso/ | 4aa9d38ee81d | jupyter-server | 2.20.0 | 1 |
| pangeo/ | 5fbe688a4f80 | jupyter-server | 2.20.0 | 1 |
| ghcr.io/ | f53bde3acd4f | jupyter-server | 2.20.0 | 1 |