CVE-2020-7674 in access-policy
Summary
by MITRE
access-policy through 3.1.0 is vulnerable to Arbitrary Code Execution. User input provided to the `template` function is executed by the `eval` function resulting in code execution.
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Analysis
by VulDB Data Team • 06/11/2020
The vulnerability identified as CVE-2020-7674 resides within the access-policy library version 3.1.0 and earlier, presenting a critical arbitrary code execution flaw that directly impacts software systems relying on this component for access control management. This vulnerability stems from the library's improper handling of user-supplied input within its template function implementation, creating a dangerous condition where untrusted data can be processed through the eval function mechanism. The flaw represents a fundamental security weakness in input validation and code execution flow control that has widespread implications for applications utilizing this access control framework.
The technical implementation of this vulnerability demonstrates a classic insecure coding pattern where user-provided data flows directly into an evaluation context without proper sanitization or validation. When the template function processes user input, it constructs code strings that are subsequently passed to the eval function, which executes them as JavaScript code within the application's runtime environment. This design flaw allows attackers to inject malicious code payloads that can execute with the privileges of the affected application, potentially leading to complete system compromise. The vulnerability maps directly to CWE-94, which categorizes improper control of generation of code, and specifically aligns with the broader category of code injection vulnerabilities that have been consistently flagged as critical threats in cybersecurity frameworks.
The operational impact of CVE-2020-7674 extends far beyond simple code execution, as it enables attackers to perform a wide range of malicious activities including data exfiltration, privilege escalation, and system infiltration. An attacker who can manipulate the template function input can execute arbitrary commands on the target system, potentially gaining access to sensitive information, modifying system configurations, or even establishing persistent backdoors. This vulnerability affects any application that depends on the access-policy library for authorization decisions, making it particularly dangerous in enterprise environments where access control is fundamental to security posture. The attack surface is broad since the vulnerability can be exploited through various input vectors including API endpoints, configuration files, or user interfaces that interact with the vulnerable template processing functionality.
Mitigation strategies for this vulnerability require immediate remediation through version updates to access-policy library 3.1.1 or later, which address the improper eval usage by implementing proper input sanitization and code execution restrictions. Organizations should conduct comprehensive vulnerability assessments to identify all systems utilizing the affected library version and prioritize patching efforts accordingly. Additional defensive measures include implementing strict input validation policies, employing secure coding practices that eliminate direct eval usage in production environments, and establishing runtime monitoring to detect suspicious code execution patterns. From an ATT&CK framework perspective, this vulnerability aligns with techniques such as T1059.007 for command and script interpreter and T1190 for exploit public-facing application, making it a significant threat vector that requires both preventive and detective security controls to effectively address the risk of unauthorized code execution in access control systems.