Signature Detail

WORM: NACHI.B\C\D Locator Infection Attempt

This signature detects infection attempts of the Windows RPC Locator Service by the B, C or D variants of the Nachi worm. This signature only triggers on a successful connect to an accessible victim. Follow up is strongly suggested.

Extended Description

It has been reported that the Microsoft Windows Locator service is affected by a remotely exploitable buffer overflow vulnerability. The condition is due to a memory copy of RPC arguments received from remote clients into a local buffer. This vulnerability may be exploited by remote attackers to execute custom instructions on the target server. It is also possible to crash the service with a malicious request. It should be noted that, to exploit this vulnerability, no authentication is required. Additionally, the Locator service is enabled by default on all Windows 2000 and Windows NT Domain Controllers (DC).

Affected Products

• Microsoft Windows 2000 Advanced Server SP1
• Microsoft Windows 2000 Advanced Server SP2
• Microsoft Windows 2000 Advanced Server SP3
• Microsoft Windows 2000 Advanced Server
• Microsoft Windows 2000 Datacenter Server SP1
• Microsoft Windows 2000 Datacenter Server SP2
• Microsoft Windows 2000 Datacenter Server SP3
• Microsoft Windows 2000 Datacenter Server
• Microsoft Windows 2000 Professional SP1
• Microsoft Windows 2000 Professional SP2
• Microsoft Windows 2000 Professional SP3
• Microsoft Windows 2000 Professional
• Microsoft Windows 2000 Server SP1
• Microsoft Windows 2000 Server SP2
• Microsoft Windows 2000 Server SP3
• Microsoft Windows 2000 Server
• Microsoft Windows 2000 Server Japanese Edition
• Microsoft Windows 2000 Terminal Services SP1
• Microsoft Windows 2000 Terminal Services SP2
• Microsoft Windows 2000 Terminal Services SP3
• Microsoft Windows 2000 Terminal Services
• Microsoft Windows NT Enterprise Server 4.0
• Microsoft Windows NT Enterprise Server 4.0 SP1
• Microsoft Windows NT Enterprise Server 4.0 SP2
• Microsoft Windows NT Enterprise Server 4.0 SP3
• Microsoft Windows NT Enterprise Server 4.0 SP4
• Microsoft Windows NT Enterprise Server 4.0 SP5
• Microsoft Windows NT Enterprise Server 4.0 SP6
• Microsoft Windows NT Enterprise Server 4.0 SP6a
• Microsoft Windows NT Server 4.0
• Microsoft Windows NT Server 4.0 SP1
• Microsoft Windows NT Server 4.0 SP2
• Microsoft Windows NT Server 4.0 SP3
• Microsoft Windows NT Server 4.0 SP4
• Microsoft Windows NT Server 4.0 SP5
• Microsoft Windows NT Server 4.0 SP6
• Microsoft Windows NT Server 4.0 SP6a
• Microsoft Windows NT Terminal Server 4.0
• Microsoft Windows NT Terminal Server 4.0 SP1
• Microsoft Windows NT Terminal Server 4.0 SP2
• Microsoft Windows NT Terminal Server 4.0 SP3
• Microsoft Windows NT Terminal Server 4.0 SP4
• Microsoft Windows NT Terminal Server 4.0 SP5
• Microsoft Windows NT Terminal Server 4.0 SP6
• Microsoft Windows NT Terminal Server 4.0 SP6a
• Microsoft Windows NT Workstation 4.0
• Microsoft Windows NT Workstation 4.0 SP1
• Microsoft Windows NT Workstation 4.0 SP2
• Microsoft Windows NT Workstation 4.0 SP3
• Microsoft Windows NT Workstation 4.0 SP4
• Microsoft Windows NT Workstation 4.0 SP5
• Microsoft Windows NT Workstation 4.0 SP6
• Microsoft Windows NT Workstation 4.0 SP6a
• Microsoft Windows XP 64-bit Edition SP1
• Microsoft Windows XP 64-bit Edition
• Microsoft Windows XP Home SP1
• Microsoft Windows XP Home
• Microsoft Windows XP Professional SP1
• Microsoft Windows XP Professional

References

• BugTraq: 6666
• CVE: CVE-2003-0003
• URL: http://vil.nai.com/vil/content/v_101013.htm
• URL: http://secunia.com/virus_information/566/nachi.b/
• URL: http://www.sophos.com/virusinfo/analyses/w32nachib.html