CVSS 3.1
9.6 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:HCVE-2026-86044
Critical (9.6) in jupyterlab jupyterlab-desktop. EPSS 0.3% estimated probability of exploitation activity in the next 30 days.
On this page
JupyterLab Desktop is the cross-platform desktop application for JupyterLab. Prior to 4.6.2-1, JupyterLab Desktop exposed getServerInfo to the renderer without confirming that the current page still had the local Jupyter server origin. In a local managed session using JupyterLab before 4.4.8, an attacker can place a crafted MathJax link in an untrusted notebook. If a victim opens the notebook and clicks the link, the existing renderer navigates to an attacker-controlled site while retaining access to the preload bridge. The site can call getServerInfo to obtain the local server URL and authentication token, then use the Jupyter REST API to create and trust a notebook that executes arbitrary code as the victim. Users whose environment already uses JupyterLab 4.4.8 or later are unaffected because the corrected link handling breaks the first step of the chain. This vulnerability is fixed in 4.6.2-1.
Severity
- EPSS
- 0.3% estimated probability of exploitation activity in the next 30 days; 24th percentile. Scored 2026-11-10. A forecast for this CVE across the internet, not for your own systems.
- CWE
- CWE-601 URL Redirection to Untrusted Site (Open Redirect)
- OWASP Top 10
- A01:2025 Broken Access Control
- Published
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Explain CVE-2026-86044 for an engineer deciding whether to act. Use https://cve.bz/api/public/cves/CVE-2026-86044?via=ask-ai-copy and https://cve.bz/cve/CVE-2026-86044?via=ask-ai-copy as the source of truth: what is affected and which versions fix it, whether it is in CISA KEV, public exploits, and its EPSS (an internet-wide 30-day estimate of exploitation activity, not a forecast for my systems). If they give no fixed versions, use the CVE record https://cveawg.mitre.org/api/cve/CVE-2026-86044 or the vendor advisory, not third-party mirrors. Tell me how to check whether I am affected and how to verify a fix. Cite the sources and say where they are uncertain.Opens a third-party assistant; its answer is its own, not cve.bz's. The prompt holds only this CVE's id and public links.
Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| jupyterlab-desktop | < 4.6.2-1 |
Attack patterns (CAPEC)
- CAPEC-178 Cross-Site Flashing Likelihood: Medium · Severity: Medium
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.