What is CVE-2026-123291?

CVE-2026-123291 is a medium-severity vulnerability in Jetbrains Datalore, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 4.3/10. Published 2026-11-06.

How severe is CVE-2026-123291?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Auth bypass in Jetbrains Datalore

CVE-2026-123291

In JetBrains Datalore before 2026.4 improper owner validation allowed reading another workspace's issues and runs notebook

Vulnerability class: IDOR (Insecure Direct Object Reference)

Published 2026-11-06 · last modified 2026-11-06.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.003 (16.4th percentile), scored 2026-11-09.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 16th percentile — 16.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

The 30-day trend appears once there are two daily scores.

Affected products

Jetbrains Datalore

Weakness classification (CWE)

CWE-639 — Authorization Bypass Through User-Controlled Key

References

www.jetbrains.com/privacy-security/issues-fixed/

Frequently asked questions

What is CVE-2026-123291?: CVE-2026-123291 is a medium-severity vulnerability in Jetbrains Datalore, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 4.3/10. Published 2026-11-06.
How severe is CVE-2026-123291?: Medium severity. CVSS v3 base score is 4.3 out of 10.