CVE-2026-123854 · Other
NO FIX YET · SEE WHAT TO DO
Before PyCharm 2026.3, a crafted Jupyter notebook widget module could execute code while PyCharm was in Safe Mode. An attacker who gets a developer to open such a notebook can run code on that developer's machine.
first public Nov 6, 2026 · 1 source
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Developers who open Jupyter notebooks in PyCharm versions before 2026.3, including notebooks from untrusted sources. The sources do not say whether the flaw needs a particular notebook feature enabled beyond opening the file. Teams that only use PyCharm on trusted notebooks face lower risk but should still upgrade.
Not affected if pycharm-2026.3-or-later
Who cares jupyter, pycharm, python
2026.3; anything earlier is in the affected range2026.3 or laterIn JetBrains PyCharm before 2026.3 code execution was possible in Safe Mode via a crafted Jupyter notebook widget module
This page as .md · .json · CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
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