Skip to content
Fencer Vulns
medium 6.1

CVE-2026-73416 json

jupyterlab: PyPI extension blocklist package-name canonicalization bypass

published 2026-07-22 3 mo ago modified 2026-09-18 51 d ago also BIT-jupyterlab-2026-73416 , EUVD-2026-58521 , GHSA-89vp-jrxv-24w8 , PYSEC-2026-3670

cvss
6.1
version 4.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.7%
EPSS 0.7% chance of exploitation in 30 days, percentile 52%
public exploits
0
none known

Summary

jupyterlab is an extensible environment for interactive and reproducible computing, based on the Jupyter Notebook Architecture. From 4.5.0 until 4.5.10 and 4.6.2, in jupyterlab/extensions/manager.py and jupyterlab/extensions/pypi.py, JupyterLab's PyPI extension manager enforces blocked_extensions_uris by comparing requested install names to blocklist entries with custom normalization that is weaker than PyPI package-name canonicalization. An authenticated user can request a PyPI-equivalent spelling such as JupyterLab.Git for a blocklisted package such as jupyterlab-git, and JupyterLab accepts the install request even though pip resolves the variant to the same package. Security impact requires an allowlist or blocklist intended to restrict package installation, the PyPI Extension Manager, and kernels and terminals that are disabled or delegated to remote hosts. The bypass lets an authenticated user install a prohibited extension, defeat integrity restrictions, and affect availability without gaining new read access. This issue is fixed in versions 4.5.10 and 4.6.2.

Patch / fix

  • pypi jupyterlab 4.5.10, 4.6.2
  • bitnami jupyterlab 4.5.10, 4.6.2
  • jupyter jupyterlab 4.5.10, 4.6.2
  • jupyterlab Debian 14 4.4.10+ds1+~3.1.0+~0.16.6+~cs1.4.4-4

debian advisories DEBIAN-CVE-2026-73416

  • python-jupyterlab openSUSE Tumbleweed 4.5.10-1.1

opensuse advisories openSUSE-SU-2026:11634-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-73416 updated cvss 6.3

jupyterlab: jupyterlab: Extension blocklist bypass via weak package-name canonicalization

  • Red Hat Migration Toolkit for Applications 8 mta/mta-solution-server-rhel9
    affected: workaround, no fix planned “Out of support scope”
  • Red Hat OpenShift AI (RHOAI) rhoai/odh-feature-server-rhel9, rhoai/odh-th06-cpu-torch210-py312-rhel9, rhoai/odh-th06-cpu-torch291-py312-rhel9, rhoai/odh-th06-rocm64-torch291-py312-rhel9, rhoai/odh-th06-cuda130-torch210-py312-rhel9, rhoai/odh-th06-cuda130-torch291-py312-rhel9, +10 more
    affected: workaround, no fix available “Fix deferred”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2 mo ago

Exploit prediction

0.66% chance of exploitation in the next 30 days, higher than 52% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 4.0 6.1 CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N
CNA 4.0 6.1 CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:H/VA:L/SC:N/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

Affected packages

ecosystem package affected fixed in
pypi jupyterlab
>=4.6.0, <4.6.2
>=4.5.0, <4.5.10
4.6.2
4.5.10
bitnami jupyterlab
>=4.5.0, <4.5.10
>=4.6.0, <4.6.2
4.5.10
4.6.2

Affected products

  • jupyterlab jupyterlab

Classification

Weakness
  • CWE-178 Improper Handling of Case Sensitivity
  • CWE-180 Incorrect Behavior Order: Validate Before Canonicalize

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.