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CVE-2026-73626 (GCVE-0-2026-73626)

Vulnerability from cvelistv5 – Published: 2026-08-13 11:28 – Updated: 2026-08-28 13:45
VLAI
Title
JupyterLab before 4.6.2 Authentication Bypass via PyPIExtensionManager
Summary
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.
Severity
7.7 (High)
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
7.5 (High)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-13 12:57 UTC
CWE
  • CWE-284 - Improper Access Control
Assigner
References
Impacted products
Vendor Product Version CPE status
jupyterlab jupyterlab Affected: 4.6.0 , < 4.6.1 (semver)
Unaffected: 4.6.1 (semver)
guessed Create a notification for this product.
jupyterlab jupyterlab Affected: 0 , < 4.5.10 (semver)
Unaffected: 4.5.10 (semver)
guessed Create a notification for this product.
Date Public
2026-07-21 00:00
Credits
de3erve-hunter MUFFANUJ krassowski
Show details on NVD website
To clipboard 

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        "cveId": "CVE-2026-73626",
        "datePublished": "2026-08-13T11:28:25.551Z",
        "dateReserved": "2026-08-13T11:17:25.160Z",
        "dateUpdated": "2026-08-28T13:45:55.401Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



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Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.