CVE-2020-26275

Open redirect vulnerability

MEDIUM
6.1
CVSS Score
Published: December 21, 2020 at 06:00 PM UTC
Updated: June 17, 2026 at 03:07 AM UTC
2 products affected across 2 vendorsJupyter ServerJupyter Server

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Severity
MEDIUM6.1
Exploit prediction
EPSS 1%

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/".

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.1.1
Affected range stops below 1.1.1, so it looks safe — our inference, not a vendor statement
v < 1.1.1
Affected range stops below 1.1.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

CVSS

6.1MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-601

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