CVE-2015-1715 in Silverlight
Summary
by MITRE
Microsoft Silverlight 5 before 5.1.40416.00 allows remote attackers to bypass intended integrity-level restrictions via a crafted Silverlight application, aka "Microsoft Silverlight Out of Browser Application Vulnerability."
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 11/30/2024
Microsoft Silverlight 5 before 5.1.40416.00 contains a critical security vulnerability that enables remote attackers to circumvent intended integrity-level restrictions through carefully crafted Silverlight applications. This vulnerability specifically affects out-of-browser applications that run with elevated privileges, creating a significant risk for system compromise. The flaw resides in how Silverlight handles application integrity checks and privilege escalation mechanisms within its runtime environment.
The technical implementation of this vulnerability stems from insufficient validation of application integrity within Silverlight's out-of-browser execution model. When applications are configured to run outside the browser environment, they typically operate with elevated privileges to access system resources and perform operations that would otherwise be restricted. However, the vulnerability allows attackers to craft malicious Silverlight applications that can bypass these security boundaries, effectively elevating their privileges and gaining access to restricted system resources. This represents a fundamental breakdown in the security model that Microsoft implemented for protecting user systems.
The operational impact of this vulnerability is severe and multifaceted across enterprise and consumer environments. Attackers can leverage this weakness to execute arbitrary code with elevated privileges, potentially leading to complete system compromise. The vulnerability affects not only individual user systems but also enterprise environments where Silverlight applications may be deployed with elevated permissions. Organizations that rely on Silverlight for business-critical applications face significant risk, as the vulnerability could enable data exfiltration, system persistence mechanisms, or lateral movement within network environments. The remote exploit nature of this vulnerability means that attackers do not require local access to the target system, making it particularly dangerous.
This vulnerability aligns with CWE-284, which addresses improper access control mechanisms, and demonstrates weaknesses in privilege management and integrity verification within application runtime environments. From an ATT&CK framework perspective, this vulnerability maps to privilege escalation techniques and can be used to establish persistent access through the execution of malicious code with elevated privileges. The vulnerability also relates to defense evasion tactics, as it allows attackers to bypass security controls that would normally prevent unauthorized system access. Organizations should prioritize immediate patching of affected Silverlight installations and consider implementing additional security controls to limit the execution of potentially malicious Silverlight applications in their environments. The remediation process requires careful consideration of existing Silverlight deployments and may involve application redesign to avoid reliance on out-of-browser execution with elevated privileges.