I know that this is a repeat thread, I could not find a solution to any previous threads: (
https://www-secure.symantec.com/connect/forums/traffic-blocked-ntoskrnlexe)
I'm stuck at evaluating if this is really a threat or not and if it should be blocked. I also don't want to create a general rule to allow all ntoskrnl traffic, but only to allow valid traffic.
Here's a excerpt from my log:
BEGIN
"""17391 4/27/2010 1:24:15 AM Allowed 10 Incoming UDP 192.168.2.4 00-16-E3-EA-29-F8 137 192.168.2.255 FF-FF-FF-FF-FF-FF 137 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 3 4/27/2010 1:23:13 AM 4/27/2010 1:23:52 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17392 4/27/2010 1:24:15 AM Allowed 10 Outgoing UDP 192.168.2.4 00-16-E3-EA-29-F8 137 192.168.2.2 00-0C-F1-D3-17-41 137 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 3 4/27/2010 1:23:13 AM 4/27/2010 1:23:52 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17393 4/27/2010 1:24:15 AM Blocked 10 Incoming TCP 192.168.2.4 00-16-E3-EA-29-F8 58800 192.168.2.2 00-0C-F1-D3-17-41 139 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 9 4/27/2010 1:23:13 AM 4/27/2010 1:24:03 AM
GUI%GUICONFIG#SRULE@NBBLOCK#BLOCK-TCP
17394 4/27/2010 1:25:16 AM Allowed 10 Incoming UDP 192.168.2.4 00-16-E3-EA-29-F8 137 192.168.2.255 FF-FF-FF-FF-FF-FF 137 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 3 4/27/2010 1:24:15 AM 4/27/2010 1:25:00 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17395 4/27/2010 1:25:16 AM Allowed 10 Outgoing UDP 192.168.2.4 00-16-E3-EA-29-F8 137 192.168.2.2 00-0C-F1-D3-17-41 137 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 3 4/27/2010 1:24:15 AM 4/27/2010 1:25:00 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17396 4/27/2010 1:25:16 AM Blocked 10 Incoming TCP 192.168.2.4 00-16-E3-EA-29-F8 58804 192.168.2.2 00-0C-F1-D3-17-41 139 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 9 4/27/2010 1:24:15 AM 4/27/2010 1:25:11 AM
GUI%GUICONFIG#SRULE@NBBLOCK#BLOCK-TCP
17397 4/27/2010 1:25:28 AM Allowed 10 Incoming UDP 192.168.2.2 00-0C-F1-D3-17-41 137 192.168.2.255 FF-FF-FF-FF-FF-FF 137 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 1 4/27/2010 1:24:26 AM 4/27/2010 1:24:26 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17398 4/27/2010 1:25:44 AM Blocked 10 Incoming TCP 192.168.2.4 00-16-E3-EA-29-F8 58805 192.168.2.2 00-0C-F1-D3-17-41 445 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 6 4/27/2010 1:24:43 AM 4/27/2010 1:25:33 AM
GUI%GUICONFIG#SRULE@NBBLOCK#BLOCK-TCP
17399 4/27/2010 1:25:44 AM Allowed 10 Outgoing UDP 192.168.2.255 FF-FF-FF-FF-FF-FF 138 192.168.2.2 00-0C-F1-D3-17-41 138 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 1 4/27/2010 1:24:43 AM 4/27/2010 1:24:43 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17400 4/27/2010 1:25:44 AM Allowed 10 Incoming UDP 192.168.2.2 00-0C-F1-D3-17-41 138 192.168.2.255 FF-FF-FF-FF-FF-FF 138 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 1 4/27/2010 1:24:43 AM 4/27/2010 1:24:43 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17401 4/27/2010 1:26:24 AM Allowed 10 Incoming UDP 192.168.2.4 00-16-E3-EA-29-F8 137 192.168.2.255 FF-FF-FF-FF-FF-FF 137 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 3 4/27/2010 1:25:22 AM 4/27/2010 1:26:13 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17402 4/27/2010 1:26:24 AM Allowed 10 Outgoing UDP 192.168.2.4 00-16-E3-EA-29-F8 137 192.168.2.2 00-0C-F1-D3-17-41 137 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 3 4/27/2010 1:25:22 AM 4/27/2010 1:26:13 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17403 4/27/2010 1:26:24 AM Blocked 10 Incoming TCP 192.168.2.4 00-16-E3-EA-29-F8 58809 192.168.2.2 00-0C-F1-D3-17-41 139 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 9 4/27/2010 1:25:22 AM 4/27/2010 1:26:18 AM
GUI%GUICONFIG#SRULE@NBBLOCK#BLOCK-TCP
17404 4/27/2010 1:27:14 AM Blocked 10 Incoming TCP 192.168.2.4 00-16-E3-EA-29-F8 58811 192.168.2.2 00-0C-F1-D3-17-41 445 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 6 4/27/2010 1:26:13 AM 4/27/2010 1:27:03 AM
GUI%GUICONFIG#SRULE@NBBLOCK#BLOCK-TCP
17405 4/27/2010 1:27:37 AM Allowed 10 Incoming UDP 192.168.2.4 00-16-E3-EA-29-F8 137 192.168.2.255 FF-FF-FF-FF-FF-FF 137 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 4 4/27/2010 1:26:35 AM 4/27/2010 1:27:14 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17406 4/27/2010 1:27:37 AM Allowed 10 Outgoing UDP 192.168.2.4 00-16-E3-EA-29-F8 137 192.168.2.2 00-0C-F1-D3-17-41 137 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 4 4/27/2010 1:26:35 AM 4/27/2010 1:27:14 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17407 4/27/2010 1:27:37 AM Blocked 10 Incoming TCP 192.168.2.4 00-16-E3-EA-29-F8 58813 192.168.2.2 00-0C-F1-D3-17-41 139 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 9 4/27/2010 1:26:35 AM 4/27/2010 1:27:26 AM
GUI%GUICONFIG#SRULE@NBBLOCK#BLOCK-TCP
17408 4/27/2010 1:28:44 AM Allowed 10 Incoming UDP 192.168.2.4 00-16-E3-EA-29-F8 137 192.168.2.255 FF-FF-FF-FF-FF-FF 137 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 3 4/27/2010 1:27:42 AM 4/27/2010 1:28:22 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17409 4/27/2010 1:28:44 AM Allowed 10 Outgoing UDP 192.168.2.4 00-16-E3-EA-29-F8 137 192.168.2.2 00-0C-F1-D3-17-41 137 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 3 4/27/2010 1:27:42 AM 4/27/2010 1:28:22 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17410 4/27/2010 1:28:44 AM Blocked 10 Incoming TCP 192.168.2.4 00-16-E3-EA-29-F8 58818 192.168.2.2 00-0C-F1-D3-17-41 139 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 9 4/27/2010 1:27:42 AM 4/27/2010 1:28:33 AM
GUI%GUICONFIG#SRULE@NBBLOCK#BLOCK-TCP
17411 4/27/2010 1:28:44 AM Blocked 10 Incoming TCP 192.168.2.4 00-16-E3-EA-29-F8 58817 192.168.2.2 00-0C-F1-D3-17-41 445 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 5 4/27/2010 1:27:42 AM 4/27/2010 1:28:33 AM
GUI%GUICONFIG#SRULE@NBBLOCK#BLOCK-TCP
17412 4/27/2010 1:29:46 AM Allowed 10 Incoming UDP 192.168.2.4 00-16-E3-EA-29-F8 137 192.168.2.255 FF-FF-FF-FF-FF-FF 137 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 3 4/27/2010 1:28:44 AM 4/27/2010 1:29:35 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17413 4/27/2010 1:29:46 AM Allowed 10 Outgoing UDP 192.168.2.4 00-16-E3-EA-29-F8 137 192.168.2.2 00-0C-F1-D3-17-41 137 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 3 4/27/2010 1:28:44 AM 4/27/2010 1:29:35 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17414 4/27/2010 1:29:46 AM Blocked 10 Incoming TCP 192.168.2.4 00-16-E3-EA-29-F8 58822 192.168.2.2 00-0C-F1-D3-17-41 139 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 9 4/27/2010 1:28:44 AM 4/27/2010 1:29:40 AM
GUI%GUICONFIG#SRULE@NBBLOCK#BLOCK-TCP
17415 4/27/2010 1:30:14 AM Blocked 10 Incoming TCP 192.168.2.4 00-16-E3-EA-29-F8 58823 192.168.2.2 00-0C-F1-D3-17-41 445 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 6 4/27/2010 1:29:12 AM 4/27/2010 1:30:03 AM
GUI%GUICONFIG#SRULE@NBBLOCK#BLOCK-TCP
17416 4/27/2010 1:30:53 AM Allowed 10 Incoming UDP 192.168.2.4 00-16-E3-EA-29-F8 137 192.168.2.255 FF-FF-FF-FF-FF-FF 137 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 3 4/27/2010 1:29:52 AM 4/27/2010 1:30:42 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17417 4/27/2010 1:30:53 AM Allowed 10 Outgoing UDP 192.168.2.4 00-16-E3-EA-29-F8 137 192.168.2.2 00-0C-F1-D3-17-41 137 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 3 4/27/2010 1:29:52 AM 4/27/2010 1:30:42 AM
GUI%GUICONFIG#SRULE@NBENABLEYOU#ALLOW-UDP
17418 4/27/2010 1:30:53 AM Blocked 10 Incoming TCP 192.168.2.4 00-16-E3-EA-29-F8 58827 192.168.2.2 00-0C-F1-D3-17-41 139 C:\WINDOWS\system32\ntoskrnl.exe Administrator HOME Default 9 4/27/2010 1:29:52 AM 4/27/2010 1:30:48 AM
GUI%GUICONFIG#SRULE@NBBLOCK#BLOCK-TCP """"
END
Any help is much appreciated.