Microsoft Active Directory Federation Services CVE-2015-1757 Privilege Escalation Vulnerability

Description

Microsoft Active Directory Federation Services is prone to a remote privilege-escalation vulnerability because it fails to sanitize user-supplied input. An attacker can exploit this issue to gain elevated privileges and perform unauthorized actions in the context of the currently logged-in user; this may aid in launching further attacks.

Technologies Affected

• Avaya Meeting Exchange - Client Registration Server 5.0
• Avaya Meeting Exchange - Client Registration Server 5.0.1
• Avaya Meeting Exchange - Client Registration Server 5.2
• Avaya Meeting Exchange - Client Registration Server 5.2.1
• Avaya Meeting Exchange - Client Registration Server 6.0
• Avaya Meeting Exchange - Client Registration Server 6.2
• Avaya Meeting Exchange - Recording Server 5.0
• Avaya Meeting Exchange - Recording Server 5.0.1
• Avaya Meeting Exchange - Recording Server 5.2
• Avaya Meeting Exchange - Recording Server 5.2.1
• Avaya Meeting Exchange - Recording Server 6.0
• Avaya Meeting Exchange - Recording Server 6.2
• Avaya Meeting Exchange - Streaming Server 5.0
• Avaya Meeting Exchange - Streaming Server 5.0.1
• Avaya Meeting Exchange - Streaming Server 5.2
• Avaya Meeting Exchange - Streaming Server 5.2.1
• Avaya Meeting Exchange - Streaming Server 6.0
• Avaya Meeting Exchange - Streaming Server 6.2
• Avaya Meeting Exchange - Web Conferencing Server 5.0
• Avaya Meeting Exchange - Web Conferencing Server 5.0.1
• Avaya Meeting Exchange - Web Conferencing Server 5.2
• Avaya Meeting Exchange - Web Conferencing Server 5.2.1
• Avaya Meeting Exchange - Web Conferencing Server 6.0
• Avaya Meeting Exchange - Web Conferencing Server 6.2
• Avaya Meeting Exchange - Webportal 5.0
• Avaya Meeting Exchange - Webportal 5.0.1
• Avaya Meeting Exchange - Webportal 5.2
• Avaya Meeting Exchange - Webportal 5.2.1
• Avaya Meeting Exchange - Webportal 6.0
• Avaya Meeting Exchange - Webportal 6.2
• Microsoft Active Directory Federation Services 2.0
• Microsoft Active Directory Federation Services 2.1

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 a successful exploit.

Run all software as a nonprivileged user with minimal access rights.
Attackers may successfully exploit client flaws in the browser through cross-site scripting vulnerabilities. When possible, run client software as regular user accounts with limited access to system resources. This may limit the immediate consequences of client-side vulnerabilities.

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 such as unexplained incoming and outgoing traffic. This may indicate exploit attempts or activity that results from successful exploits.

Do not follow links provided by unknown or untrusted sources.
Web users should be cautious about following links to websites that are provided by unfamiliar or suspicious sources. Filtering HTML from emails may help remove a possible vector for transmitting malicious links to users.

Set web browser security to disable the execution of JavaScript.
Since exploiting cross-site scripting issues often requires the execution of malicious script code in web clients, consider disabling script code and active content support within a client browser as a way to prevent a successful exploit. Note that this mitigation tactic might adversely affect legitimate websites that rely on the execution of browser-based script code.

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