CVE-2026-64815 in IntelliJ IDEA
Summary
by MITRE • 07/23/2026
In JetBrains IntelliJ IDEA before 2026.2 arbitrary code injection was possible via UI Designer form files
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Analysis
by VulDB Data Team • 07/23/2026
JetBrains IntelliJ IDEA versions prior to 2026.2 contained a critical vulnerability that allowed arbitrary code execution through UI Designer form files, representing a significant security risk for developers working with graphical user interface components. This vulnerability stemmed from insufficient input validation and sanitization within the IDE's form designer functionality, which permitted malicious actors to inject harmful code into design files that would subsequently be executed during development or deployment processes. The flaw specifically affected the handling of serialized form data within .form files, which are used by IntelliJ IDEA's UI Designer to store graphical interface layouts and component configurations.
The technical implementation of this vulnerability exploited weaknesses in how IntelliJ IDEA processed serialized objects within form files, particularly when deserializing data structures that contained malicious payloads. Attackers could craft specially designed form files containing serialized Java objects with malicious code that would execute when the IDE loaded these files, potentially leading to remote code execution on the developer's machine. This represents a classic deserialization vulnerability where untrusted input is directly processed without proper validation, making it particularly dangerous in development environments where developers often trust IDE-generated files implicitly. The vulnerability aligns with CWE-502 which specifically addresses deserialization of untrusted data and can be mapped to ATT&CK technique T1059.007 for execution through scripting languages within development tools.
The operational impact of this vulnerability extended beyond simple code injection, potentially allowing attackers to compromise entire development environments where IntelliJ IDEA was used. Developers working with UI Designer form files could unknowingly execute malicious code when opening compromised projects, leading to data exfiltration, system compromise, or further attack vector establishment. The risk was particularly elevated in corporate environments where developers might be working on sensitive projects and where the IDE's trusted file handling behavior could be exploited by attackers who gained access to project repositories containing malicious form files. Organizations using IntelliJ IDEA for development work faced potential exposure through supply chain attacks or compromised development workflows.
Mitigation strategies for this vulnerability required immediate patching of IntelliJ IDEA installations to version 2026.2 or later, which included enhanced input validation and secure deserialization practices within the UI Designer component. Administrators should also implement strict access controls on project repositories and conduct regular security reviews of IDE configuration settings to prevent unauthorized modifications to form files. Additional protective measures included enabling secure development practices such as code signing for form files, implementing network segmentation to limit exposure, and establishing incident response procedures specifically addressing IDE-based vulnerabilities. Organizations should consider implementing automated scanning tools that can detect potentially malicious form file content and establish security awareness training for developers regarding the risks of opening untrusted IDE files. The vulnerability demonstrates the importance of securing development tooling environments as they represent critical attack surfaces in modern software development workflows.