CVE-2025-61669 — jupyter_server next parameter open redirect can redirect users to external domains
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 …
Published: 2026-05-05 · CVSS: 6.3 · CVSS 4.0
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7