Microsoft .NET Framework CVE-2015-6115 ASLR Security Bypass Vulnerability

Description

Microsoft .NET Framework is prone to a security-bypass vulnerability. An attacker can leverage this issue to bypass certain security restrictions and execute arbitrary code by exploiting another vulnerability in the application.

Technologies Affected

• Microsoft .NET Framework 2.0 SP2
• Microsoft .NET Framework 3.5
• Microsoft .NET Framework 3.5.1
• Microsoft Windows 10 for 32-bit Systems
• Microsoft Windows 10 for x64-based Systems
• Microsoft Windows 10 version 1511 for 32-bit Systems
• Microsoft Windows 10 version 1511 for x64-based Systems
• Microsoft Windows 7 for 32-bit Systems SP1
• Microsoft Windows 7 for x64-based Systems SP1
• Microsoft Windows 8 for 32-bit Systems
• Microsoft Windows 8 for x64-based Systems
• Microsoft Windows 8.1 for 32-bit Systems
• Microsoft Windows 8.1 for x64-based Systems
• Microsoft Windows Server 2008 R2 for Itanium-based Systems SP1
• Microsoft Windows Server 2008 R2 for x64-based Systems SP1
• Microsoft Windows Server 2008 for 32-bit Systems SP2
• Microsoft Windows Server 2008 for Itanium-based Systems SP2
• Microsoft Windows Server 2008 for x64-based Systems SP2
• Microsoft Windows Server 2012
• Microsoft Windows Server 2012 R2
• Microsoft Windows Vista SP2
• Microsoft Windows Vista x64 Edition SP2

Recommendations

Block external access at the network boundary, unless external parties require service.
If global access isn’t needed, filter access to the affected computer at the network boundary. Restricting access to only trusted computers and networks might greatly reduce the likelihood of exploits.

Run all software as a nonprivileged user with minimal access rights.
To reduce the impact of latent vulnerabilities, run the application with the minimal amount of privileges required for functionality.

Deploy network intrusion detection systems to monitor network traffic for malicious activity.
Deploy NIDS to monitor network traffic for signs of anomalous or suspicious activity. This includes but is not limited to unexplained incoming and outgoing traffic. This may indicate exploit attempts or activity that results from successful exploits.

Implement multiple redundant layers of security.
Various memory-protection schemes (such as nonexecutable and randomly mapped memory segments) may hinder an attacker’s ability to exploit this vulnerability to execute arbitrary code.

Updates are available. Please see the references or vendor advisory for more information.