| Event Id | 15108 |
| Source | Microsoft ISA Server Control |
| Description | ISA Server detected a spoof attack from Internet Protocol (IP) address IP_address. A spoof attack occurs when an IP address that is not reachable via the interface on which the packet was received. If logging for dropped packets is set, you can view details in the packet filter log. |
| Event Information | br>CAUSE: This behavior may occur if both of the following conditions are true: The internal network adapter on the ISA Server computer points to a default gateway address that is on the internal network. The network adapter on the server that has the published resource points to the same internal default gateway address as the ISA Server computer. RESOLUTION: 1. If there are other internal networks that send and receive traffic through the ISA Server computer, use the route add command with the -p switch to add a persistent static route to each internal network. When you specify the gateway address, point to the internal router that permits access to the other internal networks. Configure persistent static routes on the internal adapter of the ISA Server computer and on the server that has the published resource. 2. Remove the default gateway address on the internal network adapter of the ISA Server computer. For ISA Server to function correctly, the internal network adapter should not have a default gateway specified. a. Click Start, point to Settings, and then click Network and Dial-up Connections. b. Right-click the internal adapter, and then click Properties. c. Click Internet Protocol (TCP/IP), and then click Properties. d. Remove the default gateway address in the Default gateway box, and then click OK two times. 3. On the server that has the published resource, configure the default gateway address to point to the internal address of the ISA Server computer. a. Click Start, point to Settings, and then click Network and Dial-up Connections. b. Right-click the internal adapter, and then click Properties. c. Click Internet Protocol (TCP/IP), and then click Properties. d. In the Default gateway box, type the internal address of the ISA Server computer, and then click OK two times. According to Microsoft : CAUSE One of the most common causes of this issue is that two |
| Reference Links | Attempts to access published resources are logged as spoof attacks with event ID 15108 in ISA Server 2000 FIX: Cannot Renew DHCP Assigned IP Address on External ISA Interface Client computers cannot access external resources, and event ID 14147 appears in the Application log in ISA Server 2004 ISA Server Detected a Spoof Attack |
Catch threats immediately
We work side-by-side with you to rapidly detect cyberthreats
and thwart attacks before they cause damage.