---
id: "CVE-2026-123307"
page: "https://infrastack.ai/live/CVE-2026-123307"
kind: "vulnerability"
aliases: ["CVE-2026-123307"]
title: "JetBrains IntelliJ IDEA: unauthenticated connection to arbitrary host via run configurations"
severity: "medium"
cvss: 6.8
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["developer-workstation", "intellij-idea", "jetbrains", "package"]
not_affected_if: ["patched-version"]
published_at: "2026-11-06T11:17:09+00:00"
first_seen_at: "2026-11-06T11:41:25+00:00"
updated_at: "2026-11-06T11:42:14+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-123307", "first_seen_at": "2026-11-06T11:41:25+00:00"}]
exploit_sources: []
---

# JetBrains IntelliJ IDEA: unauthenticated connection to arbitrary host via run configurations

Link for people: https://infrastack.ai/live/CVE-2026-123307 (this .md is for agents)

Before IntelliJ IDEA 2026.3 and 2026.2.4, run configurations could make the IDE connect to an arbitrary host without authentication. An attacker who can supply a run configuration can use the IDE to reach hosts of their choosing.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the IntelliJ IDEA version under Help > About, or run `idea --version` if available.
- Confirm whether the installed version is earlier than `2026.3` or `2026.2.4`.

## Fix

- JetBrains IntelliJ IDEA: move to `2026.3` or `2026.2.4`.

## Timeline

- 2026-11-06T11:41:25+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-123307

## From the sources

In JetBrains IntelliJ IDEA before 2026.3, 
2026.2.4 unauthenticated connection to an arbitrary host via run configurations was possible

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_