CVE-2025-61669
Jupyter Server has an open redirection vulnerability in `next` query parameter
6.1
MEDIUM
CVSS 3.1
EPSS 0.01%
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.
How to fix CVE-2025-61669
To remediate CVE-2025-61669, upgrade the affected package to a fixed version below.
- —no fix listed
- —upgrade to 2.18.0 or later
- —upgrade to 2.18.0 or later
Is CVE-2025-61669 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (3)
- from 0
- from 0, < 2.18.0
- from 0, < 2.18.0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N |
| osv | CVSS 3.1 | MEDIUM6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |