{"id":"CVE-2026-73626","state":"PUBLISHED","title":"JupyterLab before 4.6.2 Authentication Bypass via PyPIExtensionManager","description":"JupyterLab versions >=4.6.0,<=4.6.1 and <=4.5.9 contain an allowlist/blocklist enforcement gap in PyPIExtensionManager.install(). A missing 'await' caused the is_install_allowed coroutine to never execute, so the extension allowlist/blocklist check was not enforced for direct callers of install(). The stock JupyterLab HTTP API and Extension Manager UI are not affected, as they perform a separate, correctly awaited check. The issue affects only deployments where a custom extension or downstream integration imports PyPIExtensionManager and calls install() directly with a package name influenced by untrusted input, an allowlist/blocklist is configured, the PyPI Extension Manager is enabled, and kernels and terminals are disabled or delegated to remote hosts. Fixed in JupyterLab 4.6.2 and 4.5.10.","publishedAt":"2026-08-13T11:28:25.551Z","updatedAt":"2026-08-28T13:45:55.401Z","severity":{"score":7.7,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","source":"VulnCheck"},"assigner":"VulnCheck","products":["jupyterlab jupyterlab"],"affected":[{"vendor":"jupyterlab","product":"jupyterlab","packageURL":"pkg:pypi/jupyterlab","defaultStatus":"unaffected","versions":[{"version":"4.6.0","status":"affected","lessThan":"4.6.1","versionType":"semver"},{"version":"4.6.1","status":"unaffected","versionType":"semver"}]},{"vendor":"jupyterlab","product":"jupyterlab","packageURL":"pkg:pypi/jupyterlab","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"4.5.10","versionType":"semver"},{"version":"4.5.10","status":"unaffected","versionType":"semver"}]}],"references":["https://github.com/jupyterlab/jupyterlab/security/advisories/GHSA-whvh-wf3x-g77j","https://www.vulncheck.com/advisories/jupyterlab-before-authentication-bypass-via-pypiextensionmanager"],"weaknesses":["CWE-284"],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/73xxx/CVE-2026-73626.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-73626","state":"PUBLISHED","datePublished":"2026-08-13T11:28:25.551Z","dateUpdated":"2026-08-28T13:45:55.401Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-08-13T11:17:25.160Z"},"containers":{"cna":{"title":"JupyterLab before 4.6.2 Authentication Bypass via PyPIExtensionManager","descriptions":[{"lang":"en","value":"JupyterLab versions >=4.6.0,<=4.6.1 and <=4.5.9 contain an allowlist/blocklist enforcement gap in PyPIExtensionManager.install(). 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Fixed in JupyterLab 4.6.2 and 4.5.10."}],"affected":[{"vendor":"jupyterlab","product":"jupyterlab","packageURL":"pkg:pypi/jupyterlab","defaultStatus":"unaffected","versions":[{"version":"4.6.0","status":"affected","lessThan":"4.6.1","versionType":"semver"},{"version":"4.6.1","status":"unaffected","versionType":"semver"}]},{"vendor":"jupyterlab","product":"jupyterlab","packageURL":"pkg:pypi/jupyterlab","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"4.5.10","versionType":"semver"},{"version":"4.5.10","status":"unaffected","versionType":"semver"}]}],"references":[{"url":"https://github.com/jupyterlab/jupyterlab/security/advisories/GHSA-whvh-wf3x-g77j","tags":["vendor-advisory"],"name":"GitHub Security Advisory (GHSA-whvh-wf3x-g77j)"},{"url":"https://www.vulncheck.com/advisories/jupyterlab-before-authentication-bypass-via-pypiextensionmanager","name":"VulnCheck Advisory: JupyterLab before 4.6.2 Authentication Bypass via PyPIExtensionManager","tags":["third-party-advisory"]}],"metrics":[{"format":"CVSS","cvssV4_0":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N","attackVector":"NETWORK","attackComplexity":"HIGH","attackRequirements":"NONE","privilegesRequired":"LOW","userInteraction":"NONE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":7.7,"baseSeverity":"HIGH"}},{"format":"CVSS","cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-284","lang":"en","description":"Improper Access Control","type":"CWE"}]}],"providerMetadata":{"shortName":"VulnCheck","orgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateUpdated":"2026-08-28T13:45:55.401Z"},"datePublic":"2026-07-21T00:00:00.000Z","cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:jupyter:jupyterlab:*:*:*:*:*:*:*:*","versionStartIncluding":"4.6.0","versionEndExcluding":"4.6.1"},{"vulnerable":true,"criteria":"cpe:2.3:a:jupyter:jupyterlab:*:*:*:*:*:*:*:*","versionEndExcluding":"4.5.10"}]}]}],"credits":[{"lang":"en","value":"de3erve-hunter","type":"reporter"},{"lang":"en","value":"MUFFANUJ","type":"finder"},{"lang":"en","value":"krassowski","type":"coordinator"}],"x_generator":{"engine":"vulncheck-endgame"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-13T12:57:37.438667Z","id":"CVE-2026-73626","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-13T12:57:46.464Z"}}]}}}