IntelliShield has updated this alert to report a decrease in intrusion prevention system activity that is related to the Microsoft Active Directory LDAP service denial of service vulnerability.
Microsoft Active Directory contains a vulnerability that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on a targeted system.
The vulnerability is due to improper handling of Lightweight Directory Access Protocol (LDAP) requests by the Active Directory LDAP service. An unauthenticated, remote attacker could exploit the vulnerability by sending malicious LDAP requests to the system. If successful, the attacker could cause the affected service to stop responding, resulting in a DoS condition.
Microsoft has confirmed the vulnerability in a security bulletin and released software updates.
Microsoft Active Directory and Active Directory Lightweight Services are affected when running on the following platforms:
Windows Vista SP 2 and prior
Windows Vista x64 Edition SP 2 and prior
Windows Server 2008 for 32-bit Systems SP 2 and prior
Windows Server 2008 for x64-based Systems SP 2 and prior
Windows 7 for 32-bit Systems SP 1 and prior
Windows 7 for x64-based Systems SP 1 and prior
Windows Server 2008 R2 for x64-based Systems SP 1 and prior
Windows 8 for 32-bit and 64-bit Systems
Windows Server 2012
Although attackers can exploit the vulnerability remotely without authentication, it is likely that many environments would require an attacker to access a trusted, internal network to initiate an attack. As a matter of best practice, most environments limit access to directory services, reducing the potential for exploitation.
Event data from Cisco Remote Management Services has detected intrusion prevention system signature activity related to this vulnerability. The data, which was captured on September 24, 2013, could indicate that exploits have occurred in the wild.
Microsoft has released a security bulletin at the following link: MS13-079
An unauthenticated, remote attacker could exploit this vulnerability to cause the Active Directory LDAP service to become unresponsive, resulting in a DoS condition. The failure of the Active Directory LDAP service may impact systems and applications that refer to the affected system for directory or login services, possibly impacting a number of other systems in the event of a successful attack.
The vulnerability is due to improper processing of LDAP requests by the Active Directory LDAP service.
An unauthenticated, remote attacker could exploit this vulnerability by sending malicious LDAP requests to the targeted system. The processing of the requests could cause the service to stop responding, resulting in a DoS condition.
Administrators are advised to apply the appropriate updates.
Administrators may consider using IP-based access control lists (ACLs) to allow only trusted systems to access the affected systems.
Administrators are advised to monitor affected systems.
Microsoft customers can obtain updates directly by using the links in the security bulletin. These updates are also distributed by Windows automatic update features and available on the Microsoft Update service. Microsoft Windows Server Update Services (WSUS), Systems Management Server, and System Center Configuration Manager can assist administrators in deploying software updates.
Version 2, September 19, 2013, 1:44 PM: IntelliShield has updated this alert to report an increase in intrusion prevention system activity that is related to the Microsoft Active Directory LDAP service denial of service vulnerability.
Version 1, September 10, 2013, 5:16 PM: Microsoft Active Directory contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code on a targeted system. Updates are available.
for 32-bit systems Base | for x64-based systems Base
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