CVE-2026-86505 in IntelliJ IDEA
Summary
by MITRE • 09/07/2026
In JetBrains IntelliJ IDEA before 2026.2.2 missing project-trust check leaked project metadata to JetBrains Marketplace
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Analysis
by VulDB Data Team • 09/07/2026
The vulnerability identified in versions of JetBrains IntelliJ IDEA prior to version 2026.2.2 represents a significant breach in the application's trust management architecture, specifically concerning how it handles untrusted projects and their interaction with external services. The core technical flaw lies in the absence or failure of a critical project-trust verification mechanism during the initialization phase when connecting to the JetBrains Marketplace. In normal operation, IntelliJ IDEA distinguishes between trusted and untrusted projects based on user-defined policies and security contexts. Trusted projects are granted broader permissions, including access to certain APIs and services that facilitate plugin installation and marketplace interactions. However, for untrusted or newly opened projects, these privileges should be strictly restricted to prevent unauthorized data exfiltration or execution of potentially malicious code embedded within the project structure. The defect allowed the application to bypass this isolation boundary, effectively treating an untrusted project as if it were fully trusted when initiating communication with the JetBrains Marketplace service.
This architectural oversight resulted in the unintended leakage of sensitive project metadata. When a user opened a project that had not been explicitly marked as trusted, or when the trust status was ambiguous due to the missing check, IntelliJ IDEA proceeded to transmit detailed information about the project's structure and contents to remote servers operated by JetBrains Marketplace. This metadata typically includes file names, directory structures, dependency lists, and potentially other contextual data that can reveal proprietary business logic, internal architecture patterns, or sensitive configuration details. The leakage occurs silently in the background as part of standard marketplace connectivity routines, meaning users may remain unaware that their project's intellectual property is being transmitted to an external entity without explicit consent or proper security validation.
The operational impact of this vulnerability extends beyond simple privacy concerns into the realm of corporate espionage and supply chain risk. For individual developers, the exposure might reveal proprietary algorithms or unique implementation details that could be analyzed by competitors if intercepted or misused. In enterprise environments, where source code is a primary asset, such metadata leakage can provide attackers with valuable reconnaissance data. Knowledge of specific library versions, internal module structures, and file naming conventions significantly lowers the barrier for subsequent attacks, allowing adversaries to craft more targeted exploits against known vulnerabilities in those dependencies. Furthermore, this behavior violates fundamental principles of least privilege and data minimization, as it exposes information that is not strictly necessary for the marketplace's core functionality of plugin discovery or installation.
From a classification perspective, this issue aligns with CWE-200: Information Exposure, where security-relevant information is disclosed to an unauthorized actor without explicit intent. It also relates to CWE-941: Misuse of Trust Boundaries, as the application failed to enforce the intended separation between trusted and untrusted execution contexts. In terms of adversary tactics, this vulnerability facilitates reconnaissance activities consistent with MITRE ATT&CK technique T1083: File and Directory Discovery, although in this case, the discovery is performed by the software itself rather than an external attacker directly accessing files. The leakage serves as a precursor to more severe compromises, potentially aiding in supply chain attacks where knowledge of project dependencies allows for targeted poisoning of third-party libraries or plugins that are subsequently installed via the marketplace.
Mitigation strategies primarily involve upgrading to JetBrains IntelliJ IDEA version 2026.2.2 or later, which includes patches to restore and enforce the missing project-trust checks. Until such an upgrade is feasible in all environments, organizations should implement strict access controls over their development workstations to prevent unauthorized individuals from opening sensitive projects on compromised systems. Additionally, network monitoring tools can be configured to detect anomalous outbound traffic patterns associated with IntelliJ IDEA's marketplace connections, particularly those involving large metadata payloads that deviate from baseline behavior. Developers should also adopt a zero-trust mindset by explicitly marking new or external projects as untrusted and reviewing plugin permissions carefully before installation. Regular audits of IDE configurations and security policies can help ensure that trust boundaries are correctly defined and enforced across the development lifecycle.