CVE-2020-11986 in NetBeans
Summary
by MITRE
To be able to analyze gradle projects, the build scripts need to be executed. Apache NetBeans follows this pattern. This causes the code of the build script to be invoked at load time of the project. Apache NetBeans up to and including 12.0 did not request consent from the user for the analysis of the project at load time. This in turn will run potentially malicious code, from an external source, without the consent of the user.
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Analysis
by VulDB Data Team • 09/09/2020
The vulnerability identified as CVE-2020-11986 resides within Apache NetBeans IDE version 12.0 and earlier, presenting a critical security risk through its project analysis mechanism. This flaw operates on the fundamental principle that build scripts must be executed to analyze gradle projects, a common practice in modern development environments. The vulnerability stems from the IDE's automatic execution of build script code during project loading without obtaining explicit user consent, creating a dangerous precedent where potentially malicious code can be executed without user awareness or approval.
The technical implementation of this vulnerability involves the automatic invocation of build script code at project load time, which represents a significant deviation from secure coding practices. According to CWE-94, this vulnerability falls under "Improper Control of Generation of Code" where the application executes code generated or provided by an external source without proper validation or user consent. The flaw essentially creates an attack surface where untrusted code can be executed within the IDE environment, potentially allowing attackers to deliver malicious payloads through compromised build scripts or by compromising external dependencies used in project builds.
The operational impact of CVE-2020-11986 extends beyond simple code execution, creating a comprehensive security risk that aligns with ATT&CK technique T1059.001 for Command and Scripting Interpreter. When users open projects containing malicious build scripts, the IDE automatically executes arbitrary code within the context of the user's environment, potentially leading to privilege escalation, data exfiltration, or system compromise. This vulnerability is particularly dangerous because it operates silently in the background, with no user awareness of the code execution occurring during project loading, making it an ideal vector for supply chain attacks where attackers compromise external dependencies or build scripts.
The security implications of this vulnerability are amplified by the fact that developers often trust their IDE environments and may not scrutinize project loading behavior. Attackers can exploit this by embedding malicious code within build scripts of legitimate projects or by compromising external repositories that provide dependencies for build processes. This vulnerability directly violates the principle of least privilege and user consent, as the IDE automatically assumes that all build script code is trustworthy. Organizations using Apache NetBeans versions prior to 12.1 should immediately implement mitigation strategies including updating to patched versions, implementing network segmentation to limit external repository access, and establishing strict code review processes for build scripts to prevent exploitation of this vulnerability.
The vulnerability represents a classic case of insufficient user consent in automated code execution environments, where the security model assumes trust in external code without proper verification mechanisms. This flaw demonstrates the importance of implementing user consent for potentially dangerous operations, particularly those involving code execution during application startup or project loading phases. The remediation approach should include both immediate version updates and the implementation of security awareness training for developers to recognize potential malicious build script patterns.