Vulnerability in jupyter-server (CVE-2026-6657)
Summary
Vulnerability in jupyter-server (CVE-2026-6657). Risk of unauthorized operations or information disclosure. Exploitable via allow_origin_pat.
Original description
The description as published by the source.
Duplicate Advisory
This advisory has been withdrawn because it is a duplicate of GHSA-24qx-w28j-9m6p. This link is maintained to preserve external references.
Original Description
A vulnerability in jupyter-server versions 1.12.0 through 2.17.0 allows an attacker to bypass CORS origin validation when the allow_origin_pat configuration is used. The issue arises from the use of re.match() for validating the Origin header, which only anchors at the start of the string. This allows attacker-controlled domains such as trusted.example.com.evil.com to pass validation against patterns intended to match trusted.example.com. The vulnerability affects multiple locations in the codebase, including CORS headers, WebSocket connections, referer validation, and login redirects, potentially enabling phishing attacks, arbitrary code execution, and unauthorized access to sensitive API responses.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-6657 has been found in jupyter-server.
Attackers can target a specific entry point like allow_origin_pat over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 8.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "jupyter-server CVE-2026-6657" on the vendor's site.
CVE-2026-6657 (jupyter-server) — CWE-346 / CVSS v3 8.8
Attack vector: remote (network-reachable) / unauthenticated
Attack surface: allow_origin_pat / Origin / trusted.example.com.evil.com / trusted.example.com
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-346) exists in jupyter-server. Attackers reach the vulnerable code path via allow_origin_pat without authentication.
Check the vendor advisory for the affected versions of jupyter-server. Attack surface: allow_origin_pat / Origin / trusted.example.com.evil.com / trusted.example.com.
Severity: High (CVSS 8.8/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'jupyter-server' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'jupyter-server' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
jupyter-serverを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-6657 jupyter-server
- Ubuntu UBUNTU-CVE-2026-6657 jupyter-server
References
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- web huntr.com
- web github.com
- web pypi.org