Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Jupyter Core (jupyter-core) versions before 5.8.1 on Windows are vulnerable. The shared %PROGRAMDATA% directory is searched for configuration files, so a local user on a shared multi-user system with an unprotected %PROGRAMDATA% can create configuration files that affect other users, which the source describes as local privilege escalation. Upgrade to jupyter-core 5.8.1 or later; restricting write access to %PROGRAMDATA% or the %PROGRAMDATA%\jupyter directory also mitigates this.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 7.3 | High | 3.1 | CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0020, the 9th percentile, on 8 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:34 UTC First seen by agentprime
- 31 Oct 2026, 14:34 UTC Confirmed by OSV