CVE-2019-1302 in ASP.NET Core
Summary
by MITRE
An elevation of privilege vulnerability exists when a ASP.NET Core web application, created using vulnerable project templates, fails to properly sanitize web requests, aka 'ASP.NET Core Elevation Of Privilege Vulnerability'.
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Analysis
by VulDB Data Team • 08/20/2020
The CVE-2019-1302 vulnerability represents a critical elevation of privilege flaw affecting ASP.NET Core web applications that utilize specific project templates. This vulnerability stems from inadequate sanitization of web requests within the application framework, creating a pathway for malicious actors to escalate their privileges within the system. The issue specifically impacts applications generated using vulnerable project templates, making it particularly concerning for organizations that rely on automated scaffolding tools for rapid application development. The flaw allows attackers to manipulate request parameters in ways that bypass normal security controls, potentially enabling them to execute arbitrary code or access restricted resources with elevated privileges. This vulnerability is classified under CWE-20 as "Improper Input Validation," which directly relates to the failure to properly sanitize user inputs that should be treated as untrusted data.
The technical exploitation of this vulnerability occurs when ASP.NET Core applications fail to adequately validate and sanitize incoming web requests that contain potentially malicious input. Attackers can craft specific HTTP requests that exploit the improper sanitization mechanisms, allowing them to bypass authentication checks or manipulate application behavior to gain unauthorized access to system resources. The vulnerability is particularly dangerous because it operates at the application layer, where attackers can leverage the framework's trust in request data to perform privilege escalation attacks. This type of vulnerability is categorized under the ATT&CK framework as T1068, "Exploitation for Privilege Escalation," since it directly enables attackers to gain higher privileges within the application environment. The flaw typically manifests when applications process user inputs without proper validation, allowing crafted payloads to be interpreted by the framework in unexpected ways that compromise the application's security boundaries.
The operational impact of CVE-2019-1302 extends beyond simple privilege escalation, as it can potentially lead to complete system compromise if the vulnerable application has access to sensitive data or system resources. Organizations running affected ASP.NET Core applications face significant risks including data breaches, unauthorized system access, and potential lateral movement within their network infrastructure. The vulnerability affects applications deployed across various environments including cloud platforms, on-premises servers, and containerized deployments, making it a widespread concern for enterprise security teams. Security incidents resulting from this vulnerability can lead to regulatory compliance violations, financial losses, and reputational damage. The impact is amplified when the vulnerable applications handle sensitive information such as user credentials, personal data, or business-critical resources, as the privilege escalation can enable attackers to access or manipulate these assets. Additionally, the vulnerability's presence in project templates means that new applications created using affected templates are inherently vulnerable, creating a cascading effect that can affect multiple applications within an organization's portfolio.
Mitigation strategies for CVE-2019-1302 focus on both immediate remediation and long-term architectural improvements. Organizations should immediately update their ASP.NET Core applications to versions that include the patched sanitization mechanisms, typically found in .NET Core 2.1.13 and later versions. The recommended approach involves upgrading the targeted framework versions and ensuring that all project templates used for application development have been updated to remove the vulnerable code patterns. Security teams should implement comprehensive input validation controls at multiple layers of the application architecture, including client-side, server-side, and API-level validation. Organizations must also conduct thorough vulnerability assessments to identify all applications using the affected project templates and prioritize remediation efforts based on risk exposure. Additional defensive measures include implementing web application firewalls, monitoring for suspicious request patterns, and establishing robust security testing procedures that include automated scanning for similar input validation vulnerabilities. The implementation of proper security controls should follow established standards such as OWASP Top 10 and NIST cybersecurity frameworks to ensure comprehensive protection against similar threats in the future.