CVE-2020-26275

Public Exploit
Open redirect vulnerability

Description

The Jupyter Server provides the backend (i.e. the core services, APIs, and REST endpoints) for Jupyter web applications like Jupyter notebook, JupyterLab, and Voila. In Jupyter Server before version 1.1.1, an open redirect vulnerability could cause the jupyter server to redirect the browser to a different malicious website. All jupyter servers running without a base_url prefix are technically affected, however, these maliciously crafted links can only be reasonably made for known jupyter server hosts. A link to your jupyter server may *appear* safe, but ultimately redirect to a spoofed server on the public internet. This same vulnerability was patched in upstream notebook v5.7.8. This is fixed in jupyter_server 1.1.1. If upgrade is not available, a workaround can be to run your server on a url prefix: "jupyter server --ServerApp.base_url=/jupyter/".

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.34%
Third-Party Advisory checkmarx.net Third-Party Advisory github.com Third-Party Advisory github.com
Affected: jupyter-server jupyter_server
Published at:
Updated at:

References

Link Tags
https://github.com/jupyter-server/jupyter_server/security/advisories/GHSA-9f66-54xg-pc2c third party advisory patch
https://github.com/jupyter-server/jupyter_server/commit/85e4abccf6ea9321d29153f73b0bd72ccb3a6bca third party advisory patch
https://pypi.org/project/jupyter-server/ product
https://advisory.checkmarx.net/advisory/CX-2020-4291 third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2020-26275?
CVE-2020-26275 has been scored as a medium severity vulnerability.
How to fix CVE-2020-26275?
To fix CVE-2020-26275, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-26275 being actively exploited in the wild?
It is possible that CVE-2020-26275 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-26275?
CVE-2020-26275 affects jupyter-server jupyter_server.
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