CVE-2026-123842: JetBrains IntelliJ IDEA arbitrary file write via symlinks in plugin extraction

CVE-2026-123842 · Severity: high · CVSS 7.1 · Published 2026-11-06

JetBrains IntelliJ IDEA is a popular integrated development environment used by software developers. A flaw in how the application extracts plugin archives allows an attacker to write arbitrary files to the system through symlink manipulation, potentially enabling code execution or system compromise.

Technologies: Jetbrains IntelliJ IDEA. Vendors: Jetbrains.

Quick answers

Is CVE-2026-123842 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-123842 being exploited in the wild.
How severe is CVE-2026-123842?
High severity, with a CVSS score of 7.1, published 6 November 2026.
Which products and versions are affected?
Jetbrains IntelliJ IDEA before 2026.3.
Is there a fix for CVE-2026-123842?
Yes: fixed in IntelliJ IDEA 2026.3 and later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-123842 attacked?
It is attacked with local access, in a web application.
Am I affected by CVE-2026-123842?
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 and later

Technical details

The vulnerability exists in IntelliJ IDEA's plugin archive extraction routine, which fails to safely handle symbolic links. An attacker can craft a malicious plugin archive containing symlinks that, when extracted, write files to arbitrary locations on the filesystem. This requires local access or social engineering to trick a user into installing a malicious plugin.

Affected products

  • JetBrains IntelliJ IDEA before 2026.3

Timeline

  • 2026-11-06: disclosed

References

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