Quick answers
- Is CVE-2026-123835 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-123835 being exploited in the wild.
- How severe is CVE-2026-123835?
- 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-2026-123835?
- Yes: fixed in Datalore 2026.4. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-123835 attacked?
- It is attacked over the network, in a web application.
- Am I affected by CVE-2026-123835?
- 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: Datalore 2026.4
Technical details
A race condition exists in JetBrains Datalore's init script upload handling that permits code execution in another user's computation context. The vulnerability stems from improper synchronization during script initialization, allowing an attacker to upload a malicious init script that executes with the privileges of the target user's computation. This requires network access but does not require authentication as the target user.
Affected products
- JetBrains Datalore before 2026.4
Timeline
- 2026-11-06: disclosed