Quick answers
- Is CVE-2026-123286 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-123286 being exploited in the wild.
- How severe is CVE-2026-123286?
- Medium severity, with a CVSS score of 5.9, published 6 November 2026.
- Which products and versions are affected?
- Jetbrains Datalore before 2026.4.
- Is there a fix for CVE-2026-123286?
- Yes: fixed in 2026.4. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-123286 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-123286?
- Check whether you run Jetbrains Datalore at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- Fixed in: 2026.4
Technical details
An improper authorization vulnerability in JetBrains Datalore before version 2026.4 allowed unauthorized disclosure of the notebook owner's file storage session token. The vulnerability requires network access and likely user interaction but does not require prior authentication. An attacker who exploits this can obtain a valid session token for file storage, potentially escalating privileges or accessing data beyond their intended scope.
Affected products
- JetBrains Datalore before 2026.4
Timeline
- 2026-11-06: disclosed