Quick answers
- Is CVE-2026-123276 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-123276 being exploited in the wild.
- How severe is CVE-2026-123276?
- High severity, with a CVSS score of 7.8, published 6 November 2026.
- Which products and versions are affected?
- Jetbrains CLion before 2026.3, before 2026.2.4.1.
- Is there a fix for CVE-2026-123276?
- Yes: fixed in CLion 2026.3, 2026.2.4.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-123276 attacked?
- It is attacked with local access, in a web application.
- Am I affected by CVE-2026-123276?
- Check whether you run Jetbrains CLion 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: CLion 2026.3, 2026.2.4.1
Technical details
CLion's Safe Mode does not properly validate GDB server debug profiles, allowing code execution through a crafted profile submitted to an IDE instance in Safe Mode. The vulnerability requires the attacker to provide malicious input via a debug configuration but bypasses the safety mechanisms intended to prevent execution during Safe Mode startup. A fix is available in CLion 2026.3 and 2026.2.4.1.
Affected products
- JetBrains CLion before 2026.3, before 2026.2.4.1
Timeline
- 2026-11-06: disclosed