CVE-2025-61669

MEDIUM

jupyter_server next parameter open redirect can redirect users to external domains

Title source: cna
STIX 2.1

Description

Jupyter Server is the backend for Jupyter web applications. In jupyter_server versions through 2.17.0, the next query parameter in the login flow is insufficiently validated in `LoginFormHandler._redirect_safe()`, which allows redirects to arbitrary external domains via values such as `///example.com`. An attacker can use a crafted login URL to redirect users to a malicious site and facilitate phishing attacks. This issue is fixed in version 2.18.0.

References (1)

Core 1

Scores

CVSS v3 6.1
EPSS 0.0001
EPSS Percentile 1.1%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact partial

Details

CWE
CWE-601
Status published
Products (3)
jupyter/jupyter_server < 2.18.0
jupyter-server/jupyter_server <= 2.17.0
pypi/jupyter-server 0 - 2.18.0PyPI
Published May 05, 2026
Tracked Since May 05, 2026