# CVE-2026-123278: JetBrains IntelliJ IDEA unauthenticated RMI endpoint code execution

Source: https://junglewise.ai/threats/cve-2026-123278-in-jetbrains-intellij-idea-before-2026-3-code-execution-was  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-06. Updated: 2026-11-06  
License: CC BY 4.0 with a link back

CVE-2026-123278 · Severity: medium · CVSS 6.7 · Published 2026-11-06

JetBrains IntelliJ IDEA is a widely-used IDE for Java and other languages. An attacker can execute arbitrary code on systems running vulnerable versions through an unauthenticated JDBC worker RMI endpoint, potentially compromising developer machines and source code.

Technologies: [Jetbrains IntelliJ IDEA](https://junglewise.ai/threats/technologies/intellij-idea). Vendors: [Jetbrains](https://junglewise.ai/threats/vendors/jetbrains).

## Quick answers

**Is CVE-2026-123278 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-123278 being exploited in the wild.

**How severe is CVE-2026-123278?** Medium severity, with a CVSS score of 6.7, published 6 November 2026.

**Which products and versions are affected?** Jetbrains IntelliJ IDEA before 2026.3.

**Is there a fix for CVE-2026-123278?** Yes: fixed in IntelliJ IDEA 2026.3. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-123278 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-123278?** Check whether you run Jetbrains IntelliJ IDEA 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 IntelliJ IDEA 2026.3

## Technical details

An unauthenticated RMI endpoint in the JDBC worker component of IntelliJ IDEA allows remote code execution without authentication. The vulnerability affects versions before 2026.3 and is exploitable over the network via the RMI interface.

## Affected products

- JetBrains IntelliJ IDEA before 2026.3

## Timeline

- 2026-11-06: disclosed

## References

- [https://www.jetbrains.com/privacy-security/issues-fixed/](https://www.jetbrains.com/privacy-security/issues-fixed/)

## Related threats

- [JetBrains IntelliJ IDEA code execution via JVM options in Safe Mode](https://junglewise.ai/threats/cve-2026-123853-in-jetbrains-intellij-idea-before-2026-3-2026-2-2-code-execution)
- [JetBrains IntelliJ IDEA code execution via Terraform File Watchers](https://junglewise.ai/threats/cve-2026-123849-in-jetbrains-intellij-idea-before-2026-3-code-execution-was)
- [JetBrains IntelliJ IDEA TLS hostname verification missing](https://junglewise.ai/threats/cve-2026-123848-in-jetbrains-intellij-idea-before-2026-3-host-name-verification)
- [JetBrains IntelliJ IDEA command execution via control characters in terminal completion](https://junglewise.ai/threats/cve-2026-123847-in-jetbrains-intellij-idea-before-2026-3-command-execution-was)
- [JetBrains IntelliJ IDEA blind SSRF in JSON Schema validation](https://junglewise.ai/threats/cve-2026-123846-in-jetbrains-intellij-idea-before-2026-3-blind-ssrf-was-possible)