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Re: Please run windows update now


From: Royce Williams <royce () techsolvency com>
Date: Mon, 15 May 2017 13:06:09 -0800

On Fri, May 12, 2017 at 10:30 AM, Royce Williams <royce () techsolvency com>
wrote:

My $0.02, for people doing internal/private triage:

- If your use of IPv4 space is sparse by routes, dump your internal
routing table and convert to summarized CIDR.

- Feed your CIDRs to masscan [1] to scan for internal port 445 (masscan
randomizes targets, so destination office WAN links won't saturate, but
local/intermediate might if you're not careful, so tune):

    sudo masscan -p445 --rate=[packets-per-second safe for your network]
-iL routes.list -oG masscan-445.out

- Use https://github.com/RiskSense-Ops/MS17-010/tree/master/scanners (the
python2 one, or the Metasploit one if you can use that internally) to
detect vuln. the python one is not* a parallelized script, so consider
breaking it into multiple parallel runners if you have a lot of scale.


Note - I've learned that the detection rate for the Python script above is
*much* lower than this nmap script. I recommend using the nmap script
instead:

https://github.com/cldrn/nmap-nse-scripts/blob/master/scripts/smb-vuln-ms17-010.nse



- If you're using SCCM/other, verify that MS17-010 was applied - but be
mindful of Windows-based appliances not centrally patched, etc. Trust but
verify.

- In parallel, consider investigating low-hanging fruit by OU
(workstations?) to disable SMBv1 entirely.

Royce

1. https://github.com/robertdavidgraham/masscan




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