CVE-2026-23528

MEDIUMCVSS 5.3/10EPSS 0.21%

Last modified

CVE-2026-23528 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. Dask distributed is a distributed task scheduler for Dask. Prior to 2026.1.0, when Jupyter Lab, jupyter-server-proxy, and Dask distributed are all run together, it is possible to craft a URL which will result in code being executed by Jupyter due to a cross-side-scripting (XSS) bug in the Dask dashboard. EPSS estimates a 0.21% chance of exploitation in the next 30 days.

Description

Dask distributed is a distributed task scheduler for Dask. Prior to 2026.1.0, when Jupyter Lab, jupyter-server-proxy, and Dask distributed are all run together, it is possible to craft a URL which will result in code being executed by Jupyter due to a cross-side-scripting (XSS) bug in the Dask dashboard. It is possible for attackers to craft a phishing URL that assumes Jupyter Lab and Dask may be running on localhost and using default ports. If a user clicks on the malicious link it will open an error page in the Dask Dashboard via the Jupyter Lab proxy which will cause code to be executed by the default Jupyter Python kernel. This vulnerability is fixed in 2026.1.0.

Metrics

CVSS 3.1
6.1/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS 4.0
5.3/10

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Probability
0.21%

10.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersions
AnacondaDask< 2026.1.0

References

Timeline

Published
Last Modified
Status
Analyzed

Frequently Asked Questions

What is CVE-2026-23528?
Dask distributed is a distributed task scheduler for Dask. Prior to 2026.1.0, when Jupyter Lab, jupyter-server-proxy, and Dask distributed are all run together, it is possible to craft a URL which will result in code being executed by Jupyter due to a cross-side-scripting (XSS) bug in the Dask dashboard. It is possible for attackers to craft a phishing URL that assumes Jupyter Lab and Dask may be running on localhost and using default ports. If a user clicks on the malicious link it will open an error page in the Dask Dashboard via the Jupyter Lab proxy which will cause code to be executed by the default Jupyter Python kernel. This vulnerability is fixed in 2026.1.0.
How severe is CVE-2026-23528?
CVE-2026-23528 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 0.21% probability of exploitation in the next 30 days.
How do I fix CVE-2026-23528?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-23528?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST