Open redirect in Jupyter Server - CVE-2025-61669
Published: May 5, 2026
Vulnerability identifier: #VU130163
CSH Severity: Medium
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2025-61669
CWE-ID: CWE-601
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to redirect users to arbitrary external domains.
The vulnerability exists due to url redirection to an untrusted site in LoginFormHandler._redirect_safe() when processing the next query parameter. A remote attacker can supply a crafted next parameter to redirect users to arbitrary external domains.
User interaction is required for a victim to follow the crafted login URL.
Affected software
Jupyter Server
How to mitigate CVE-2025-61669
Install security update from vendor's website.
Jupyter Server - update to 2.18.0