Marc Kranat

15 posts

CISM CISSP Marc Kranat is Sucuri’s Enterprise Firewall Supervisor who joined the company in 2014. Marc’s main responsibilities include providing support to high-value clients. His professional experience covers over 20 years in cyber and IS security and project management. When Marc isn’t checking firewall logs and configurations, you might find him acting as an assistant to his photographer wife, or wranging his Husky. Connect with him on Twitter.

90 Days to Shine: Why Sucuri’s SSL Certificates Are Living the Short Life (and Why That’s Awesome)

Marc Kranat
May 16, 2025

Picture this: your SSL certificate is like a carton of milk in your fridge. Sure, it’s good for a while, but let it sit too…

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What is HTTP 504 Gateway Timeout & How to Fix It

Marc Kranat
May 14, 2024

Website errors can be extremely frustrating, and one that often appears is the 504 Gateway Timeout error. This error occurs when an upstream server fails…

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What is HTTP Error 502 Bad Gateway & How to Troubleshoot It

Marc Kranat
May 9, 2024

Website errors can be a real test of patience. One common culprit is the 502 bad gateway error. Known for its ubiquity across the web,…

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Troubleshooting ERR_SSL_PROTOCOL_ERROR: How to Fix the SSL Protocol Error in 6 Steps

Marc Kranat
February 6, 2024

As a website owner (and frequent website visitor), you might have encountered the notorious ERR_SSL_PROTOCOL_ERROR at least once.

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HTTPS Protocol: What is the Default Port for SSL & Common TCP Ports

Marc Kranat
November 28, 2023

SSL port numbers serve as communication endpoints for transmitting or receiving data. One of the primary functions of these ports is to establish a secure…

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Why Your IP Address is Blocked & How to Fix It

Marc Kranat
June 6, 2023

Imagine this scenario: You’re sipping a delightful cup of tea (I’m English) while catching up on the latest news when suddenly – wham! You find…

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Problems with Email Server after Malware Infection

Help! My Email Server Got B0rked & I Have Problems After Malware Infection!

Marc Kranat
February 14, 2023

The Sucuri Firewall functions as a reverse proxy. A simple change to your DNS settings is all it takes to thoroughly filter incoming traffic to…

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Bad Paths & The Importance of Using Valid URL Characters

Marc Kranat
January 10, 2023

To ensure that your web files and pages are accessible to a wide range of users with various different devices and operating systems, it’s important…

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Poodle and Doodle, FUD and the Sucuri WAF

Marc Kranat
April 19, 2022

On any given day, Sucuri sees thousands of clients go through the PCI compliance process. The requirements outlined by the Payment Card Industry Data Security…

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UCEPROTECT Scam: When RBLs Go Bad

Marc Kranat
February 12, 2021

What is a Realtime Blackhole List (RBL)? A Realtime Blackhole List (RBL) contains lists of email servers, domain names, and IP addresses that are associated…

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