Collaborate Disseminate
I have a server which have configured Amavis and Spamassasin (in default state only). I recently noticed log lines that probably indicate DNS query failure, below is an excerpt:
Nov 21 11:15:40 spamfilter-1 amavis[4029071]: (4029071-15) p0… Continue reading Why spamassasin is doing dns lookup?
PolarDNS is a specialized authoritative DNS server that allows the operator to produce custom DNS responses suitable for DNS protocol testing purposes. What can you do with PolarDNS? PolarDNS can be used for testing of: DNS resolvers (server-side) DNS … Continue reading PolarDNS: Open-source DNS server tailored for security evaluations
So I’m using Active Campaign as a CRM and have configured DKIM, SPF, and a DMARC none policy. I am having one particular customer of mine that’s not able to receive my emails despite them whitelisting me. They are using mimecast. I’ve don… Continue reading How To Address Email Deliverability Problems When From Header Doesn’t Match From Envelope?
For SOC teams to be able to defend their organization against ransomware attacks, they need to have the right security toolset, but also an understanding of the three primary ransomware attack stages. In this article, we will dive into those key stages… Continue reading The 3 key stages of ransomware attacks and useful indicators of compromise
If a domain, for example foo.com is pointed to a IP address (A record) outside of my control, for example the Twitter IP address. And the domain is visited using a browser:
What will be displayed in the browser?
Does it make sense for com… Continue reading What happens if a DNS record points to non-controlled IP address?
Android has the option for using private DNS, but it requires a hostname, not an IP of the DNS server. Isn’t entering the domain name of a DNS server a chance for MITM attacks and DNS poisoning?
How is using a hostname secure?
Continue reading Is Android private DNS using domain name a security risk?
When I turn on Warp provided by Cloudflare or use 1.1.1.1, it unlocks some of the websites which are geo locked. How does it unblock the websites which are blocked by ISP?
Continue reading Why does turning on encrypted DNS unblock some geo locked websites?
It’s always DNS. That’s what the famous internet meme popular among sysadmins says anyway. It’s funny because while clearly, every network issue doesn’t resolve to some funky DNS issue, too many network admins have banged their heads against their keyb… Continue reading Reinforcing cybersecurity: The network’s role to prevent, detect, and respond to attacks
Modern-day attack surface management (ASM) can be an intimidating task for most organizations, with assets constantly changing due to new deployments, assets being decommissioned, and ongoing migrations to cloud providers. Assets can be created and for… Continue reading DIY attack surface management: Simple, cost-effective and actionable perimeter insights
I am trying to figure out the best way to manage security certificates for embedded devices who’s webpage is accessed via IP address, and then the scenario for when that IP address changes.
Currently, I am creating an RSA private key to si… Continue reading Is it reasonable to have a product that requires LLMNR or mDNS?