XCK and CRK file formats for binary patching in Windows.

Do not bother Googling these file types as they belong with the era before Google even existed. In these pre-Google Dark Ages there were people taking pride in circumventing software protections or cracking in other words, and believe or not – absolutely for free. Yep, even DMCA didn’t exist back …



NMAP UDP DNS scan unexpected packets sending

I got the other day an automated mail alert from some ID/IPS equipment that ‘ a NULL DNS scan was detected and blocked from your IP’. NULL DNS scan? I wasn’t sending any such packets, not to mention I have no idea what they mean by that. After some …



Last measure for the desperate case of a lost access to the Check Point firewall

It may happen to anyone – mistaken security rule “Any Any Drop”, or using dynamic object for URL block. The end result – after the policy install you have no administrative access to the firewall with SmartDashboard/ssh/https. For this case Check Point came with fw unloadlocal console/SSH expert level …



How many times can we change IP address of the Check Point license?

Today most licenses are of a central type so we rarely need to change their IP address as IP address of the Management server does not change that often. Still, if this happens then there is an option to change IP address or re-license the existing license. Don’t take …



NMAP run stages flow diagram

NMAP scanner has become over the years so friendly that it is not apparent what is going on when it runs. Below is a typicsl NMAP workflow:



Hex editor of binary files on Linux

Reading this thread on Stackoverflow http://stackoverflow.com/questions/5498197/need-a-good-hex-editor-for-linux I wondered how come with so many hex editors in Linux there is not really the best one. In Windows it is easier - the expensive WinHex or the cheap Hview. Anyway, as to the Linux I always use Vim …



Ever wondered how much does ip addresses allocation cost to your service provier ?

Ever wondered how much does IP addresses allocation really cost to your provider? Well, that is easy. If we talk about the RIPE IP address space (majority today) then they have published their fees for PI (Provider Independent) allocations for LIRs (Local Internet Registry) which is by coincidence your ISP …



Public DNS servers open to any on the Internet

Following the good will by Google many other providers made their DNS servers available to us without any limitations as recursive resolvers. As they do not announce it widely enough you may not have heard abouth them, here is the list of these DNS servers: - OpenDNS: 208.67.222.220 …



Linux ip route command reference by example

# ip address show - show all IP addresses (also ip ad sh) # ip address show ens36 - show IP addresses of a particular interface # ip address show up - only show IPs of those interfaces that are up # ip address show dynamic|permanent - show dynamic or static IPv6 addys # ip address add 192 …



Free public NTP servers from Google

It has passed somewhat unnoticed but Google have made available to us their free, accessible to all NTP servers. I have been using their DNS servers for years without any issues so will trust their NTP ones as well. So far works just fine. For a single server we can …