Description

In JetBrains IntelliJ IDEA before 2026.3 improper checks could enable disabled plugins via external dependency settings

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "3.3",
  "pubDate": "2026-11-06T11:17:10.593Z",
  "pubdate": "2026-11-06T11:17:10.593Z",
  "executiveSummary": "A security vulnerability exists in JetBrains IntelliJ IDEA versions prior to 2026.3 involving the improper validation of external dependency settings.\nThe flaw allows for the unauthorized activation of plugins that were previously explicitly disabled by the user or system administrator.\nBy manipulating external dependency configurations, an attacker can force the initialization of malicious or restricted plugins, potentially leading to arbitrary code execution, unauthorized access to development environments, or the exfiltration of sensitive source code and credentials.\nThis vulnerability highlights a failure in the application's integrity enforcement mechanism regarding plugin state management.\nExploitation requires the ability to influence or modify external dependency settings associated with the IDE environment.\nThe impact is significant, as it circumvents established security policies intended to sandbox or isolate non-trusted plugin components within the IDE ecosystem.",
  "technicalDetails": "The vulnerability originates from inadequate validation logic within the IntelliJ IDEA configuration parser, specifically concerning the interaction between external dependency management and the local plugin registry state.\nIn affected versions, the IDE fails to enforce a strict immutable state for plugins marked as 'disabled.' When the IDE processes external dependency manifests—commonly ingested through project configuration files or workspace settings—the internal plugin manager does not cross-reference the incoming dependency requests against the current local security policy.\nThe root cause lies in a logic flaw where the plugin loader prioritizes the requirements dictated by external dependency metadata over the existing user-defined disabled status. During the workspace loading phase, the IDE parses these dependencies and, due to the missing constraint check, proceeds to initialize and load plugins that should have remained dormant.\nAn attacker can exploit this by crafting a malicious project configuration file that lists a disabled or potentially harmful plugin as a required external dependency. Upon opening the project, the IDE, trusting the external configuration, attempts to satisfy this dependency by triggering the plugin's lifecycle methods. This bypasses the protective measures intended to keep unauthorized or insecure plugins from executing within the host process.\nThe attack flow follows a sequential pattern: 1) Identification of a plugin intended to be disabled or currently in a disabled state. 2) Creation or modification of a project-level configuration file that defines this plugin as an external dependency. 3) The target user imports or opens the project in an affected version of IntelliJ IDEA. 4) The plugin loader, failing to sanitize the external dependency request, triggers the class loading and execution of the disabled plugin. 5) Execution of the plugin's initialization logic occurs within the context of the IDE process.\nThe scope of post-exploitation activity is limited only by the permissions granted to the IntelliJ IDEA process itself. Since the plugin is executing with the same security context as the IDE, it can gain full access to the underlying filesystem, network stack, and sensitive information stored within the IDE's configuration folders, including encrypted authentication tokens and project environment variables."
}