CVE-2025-61669: jupyter-server jupyter_server Open Redirect
Vulnerability summary
CVE-2025-61669 is a medium (CVSS 6.3) Open Redirect vulnerability in jupyter-server jupyter_server. EPSS estimates a 0.24% chance of exploitation in the next 30 days, higher than 14.6% of scored vulnerabilities. 1 public exploit is recorded.
Advisory lineage
Upstream 0 · Downstream 1 · Related 2Timeline
- 05-05-2026PublishedVulnerability first disclosed.
- 05-05-2026Last modifiedVulnerability information updated.
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.
CVSS metrics
8 scores · 6 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated6.3MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N
- OSV · ChainguardEcosystem advisory · calculated6.3MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N
- NVDNIST6.3MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- OSV · UbuntuEcosystem advisory · calculated6.1MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- OSV · DebianEcosystem advisory · calculated6.1MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- NVDNIST6.1MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS trend
Probability
0.24%
Chance of exploitation in the next 30 days
Percentile
15%
Versus all other CVEs
30-day change
-0.02 pp
From 0.27% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundJupyter Server
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Chainguard2 products
- datahub-ingestion< 1.5.0.4-r0
- datahub-ingestion-fips< 1.5.0.1-r2
Debian1 product
- jupyter-serverAll versions (No fix recorded) | < 2.20.0-1
Jupyter1 product
- jupyter_server< 2.18.0
Jupyter-server1 product
- jupyter_server≤ 2.17.0
PyPI1 product
- jupyter-server< 2.18.0
Ubuntu1 product
- jupyter-serverAll versions (No fix recorded)
6 vendors · 7 products
References
8 links- github.com/jupyter-server/jupyter_server/security/advisories/GHSA-qh7q-6qm3-653wX Refsource CONFIRMWEBEVIDENCEREPORTAdvisoryExploitVendor Advisory
