Cisco IOS-related CVEs get announced consistently, but we will not be exploring any of those in this article. I will, however, demonstrate that attacking a Cisco IOS device is possible with SNMP misconfiguration. If interested, I covered another attack on a Cisco IOS device running HSRP here. I included this exercise on our Paradise Lost: Red Team versus Blue Team event during our CyberFest 2021. Unfortunately, only the blue team members touched this node. The red team focused on …
Network Security
Defending against SSH brute force attacks
I was a victim of SSH brute force attacks, which I covered here. As a result, I discovered a great solution without using SSH keys. As another layer of security, I added two-factor authentication to my server. A few years ago, I wondered if there was a solution in Cisco IOS. I discovered a security feature called login enhancements or login block. Let's look at how it can help defend from SSH brute force attacks by enabling this feature. What is login block? It is a Cisco …
[Read more...] about Defending against SSH brute force attacks
Securing Cisco IOS passwords
Over the years, Cisco has made improvements in storing passwords in the configuration file. As a result, securing Cisco IOS passwords is part of my checklist when hardening Cisco-based network infrastructure for clients. This article also appeared on Art of Network Engineering. History Cisco IOS has always had the option to store passwords in cleartext in the configuration file. As you and I both know, storing passwords in the configuration file is a big no-no. That said, …
Penetration Testing 101 – CTF Edition
As mentioned in my previous article, I participated in a CTF competition. Part of that CTF competition included OSINT (Open-Source Intelligence) and penetration testing exercises. Today, I want to discuss penetration testing 101 in a CTF environment. Pre-engagement Pentesting in the real world starts with the pre-engagement phase. This phase involves engaging with the client to find out their goals, scope of work, etc. It's different in a CTF environment. Some CTF will give you the …
Attacking HSRP
Back in the day, the Cisco Press books only covered the Hot Standby Router Protocol (HSRP) topic in the professional-level track. When I did a quick search on CCNA books, I found out that they covered it in CCNA R&S ICND2 200-105 OCG* and the new CCNA 200-301 OCG, Vol 2* books. Both books, however, didn't cover the security vulnerability of such minimal configuration. Thus, attacking HSRP is possible. This post contains affiliate links. If you use these links to buy …