---
id: "CVE-2026-123844"
page: "https://infrastack.ai/live/CVE-2026-123844"
kind: "vulnerability"
aliases: ["CVE-2026-123844"]
title: "JetBrains IntelliJ IDEA: custom plugin repositories allow server-side request forgery"
severity: "medium"
cvss: 5.3
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["ide", "intellij-idea", "java", "jetbrains", "package"]
not_affected_if: ["default-plugin-repository-only", "version-2026.3-or-later"]
published_at: "2026-11-06T17:17:23+00:00"
first_seen_at: "2026-11-06T17:43:13+00:00"
updated_at: "2026-11-06T17:45:32+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-123844", "first_seen_at": "2026-11-06T17:43:13+00:00"}]
exploit_sources: []
---

# JetBrains IntelliJ IDEA: custom plugin repositories allow server-side request forgery

Link for people: https://infrastack.ai/live/CVE-2026-123844 (this .md is for agents)

IntelliJ IDEA before 2026.3 could be made to send server-side requests to addresses an attacker chooses through custom plugin repository settings. An attacker could use the IDE to reach internal services the developer's machine can see.

_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; versions before `2026.3` are affected.
- Check whether custom plugin repositories are configured under Settings > Plugins > Manage Plugin Repositories.

## Fix

- Move IntelliJ IDEA to `2026.3` or later.

## Timeline

- 2026-11-06T17:43:13+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-123844

## From the sources

In JetBrains IntelliJ IDEA before 2026.3 sSRF was possible via custom plugin repositories

---

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