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- Demo of cyber security risk of XSSWhat is XSS and Why Is It Risky? XSS happens when a website doesn’t properly “clean” (sanitize) user inputs, like search queries or comments. An attacker can inject JavaScript code, which runs when you visit the page. Risks include: Real-world examples: In 2018, hackers used XSS on British Airways’ site to steal credit card details… Read more: Demo of cyber security risk of XSS
- Top 5 Critical Cybersecurity Incidents in July 2025As we navigate through 2025, the cybersecurity world is buzzing with activity, and not the good kind. July has brought a wave of high-impact incidents that have shaken industries from tech to healthcare. These breaches and attacks not only expose vulnerabilities but also highlight the ever-evolving tactics of cybercriminals. In this blog post, I’ll dive… Read more: Top 5 Critical Cybersecurity Incidents in July 2025
- Introduction to Selected Regex FlavorsRegex flavors are dictated by runtime environments. Online testers often prioritize these five due to their dominance: Differences arise from historical updates (e.g., PCRE2’s improvements over PCRE) and design goals (e.g., ECMAScript’s web safety vs. Python’s readability). In 2025, with PHP 7.3+ adoption at ~85% (per W3Techs surveys), PCRE2 is standard, but legacy PCRE persists… Read more: Introduction to Selected Regex Flavors
- IP calculator (Ipv4 & Ipv6)IPv4 Subnet Calculator IP Address: Subnet Mask (CIDR or Dotted Decimal): Calculate IPv6 Subnet Calculator IPv6 Address: Prefix Length (CIDR): Calculate IPv4 and IPv6 Calculator In the realm of networking and cybersecurity, managing IP addresses is fundamental to building resilient systems. An IPv4 and IPv6 Calculator is a powerful tool that performs essential calculations like… Read more: IP calculator (Ipv4 & Ipv6)
- Difference of CHAP and PAPIn network security and authentication mechanisms, understanding protocols such as the Password Authentication Protocol (PAP) and the Challenge-Handshake Authentication Protocol (CHAP) is essential for IT professionals. These protocols are integral to Point-to-Point Protocol (PPP) implementations, commonly utilized in remote access services, virtual private networks (VPNs), and wide area network (WAN) connections. This article provides a… Read more: Difference of CHAP and PAP
- Understanding HTTP GET vs POST: Differences, Examples, and Security ConcernsWhen developing web applications, choosing between HTTP GET and POST methods is crucial. These methods handle data differently, impacting functionality, user experience, and security. In this blog post, we’ll dive into the key differences between GET and POST, provide practical examples, and explore security concerns—particularly why using POST instead of GET might introduce risks. We’ll… Read more: Understanding HTTP GET vs POST: Differences, Examples, and Security Concerns
- Understanding “Is” vs “Has Been” for BeginnersToday, I’m sharing a quick and easy lesson to help you understand the difference between “is” and “has been“—two tricky terms that often confuse beginners. Don’t worry, I’ve got you covered with clear explanations and examples! What’s This Lesson About? In this post, we’ll dive into: 1. “Is” – For Current States Use “is” when… Read more: Understanding “Is” vs “Has Been” for Beginners
- URL Filtering with Deep Packet Inspection (DPI) on Palo Alto FirewallsIn modern network security, URL filtering is essential for controlling and monitoring web access. When an explicit proxy is paired with a Palo Alto Networks firewall and Deep Packet Inspection (DPI)—typically involving SSL/TLS decryption—is enabled, the firewall can perform highly granular URL filtering. This post dives into how URL filtering works in this setup, the… Read more: URL Filtering with Deep Packet Inspection (DPI) on Palo Alto Firewalls
- Overview of URL Filtering – Without DecryptionPalo Alto Networks firewalls use their PAN-DB cloud-based URL filtering database (or an offline PAN-DB private cloud in some cases) to categorize websites and enforce policies based on those categories. Even when SSL/TLS traffic is not decrypted, the firewall can identify the destination URL or domain by analyzing unencrypted metadata in the HTTPS handshake. This… Read more: Overview of URL Filtering – Without Decryption
- Understanding Packet Filtering and Stateful FirewallsWe know that firewalls are the backbone of network security, and understanding how they process traffic is critical for designing robust defenses. Two key concepts in this domain are packet filtering and stateful firewalls. In this post, we’ll dive into how these mechanisms work, their differences, and why stateful firewalls are a staple in modern… Read more: Understanding Packet Filtering and Stateful Firewalls
- Cisco ISE vs Aruba ClearPass1. TACACS+ for Network EquipmentTACACS+ (Terminal Access Controller Access-Control System Plus) is used for centralized authentication, authorization, and accounting (AAA) for network device management. 2. Access Switchport Security ControlAccess switchport security control, typically achieved through 802.1X authentication, MAC Authentication Bypass (MAB), or other mechanisms, ensures only authorized devices connect to switch ports. 3. Other Considerations… Read more: Cisco ISE vs Aruba ClearPass
- AA(Active/Active) vs AP(Active/Passive) Palo Alto FirewallsIn today’s high-performance enterprise networks, ensuring firewall redundancy and scalability is critical. Palo Alto firewalls offer two high-availability (HA) modes: active/passive (A/P) and active/active (A/A). While A/P is simpler, A/A is gaining traction for complex environments, such as data centers with multiple WAN routers and spine-and-leaf architectures. In this post, I’ll dive into the pros… Read more: AA(Active/Active) vs AP(Active/Passive) Palo Alto Firewalls
- Fixing Certificate Errors for Web browsing via FortiGate Explicit ProxyAn issue where users accessing certain websites through a FortiGate explicit proxy (with the FortiGate CA certificate imported into client browsers) encounter certificate errors. The FortiGate logs show: “Re-signed server certificate as untrusted due to security problem.” After digging deeper, I found the root cause: the affected websites’ servers are missing intermediate certificates, causing the… Read more: Fixing Certificate Errors for Web browsing via FortiGate Explicit Proxy
- What Are Articles (The A An)?Articles are words placed before nouns to indicate whether the noun is specific or general: Types of Articles and Their Rules Table of Articles in English Article Type Usage Examples The Definite Specific nouns (singular/plural, countable/uncountable); unique items; superlatives “The car,” “The stars,” “The best movie” A Indefinite Singular, countable nouns with consonant sounds; non-specific… Read more: What Are Articles (The A An)?
- Learn “SVO” and “Parts of Speech” with a Networking ConceptConfused about Subject, Verb, Object (SVO) versus the 8 parts of speech. A friend said SVO is all I need, but the parts of speech add the real magic! Think of SVO as the basic idea of a routing protocol in networking, like moving data from point A to B. The parts of speech? They’re… Read more: Learn “SVO” and “Parts of Speech” with a Networking Concept
- FortiGate Explicit Proxy Issue with FQDN Resolution to IPv6 (FortiOS 7.4.7)We recently encountered a perplexing issue with the explicit proxy configuration on our FortiGate 121G running FortiOS 7.4.7, specifically when using an FQDN to resolve an upstream proxy. I’m sharing our findings and Fortinet TAC’s response to help others who might face similar challenges. Issue Overview In our setup, we configured the explicit proxy to… Read more: FortiGate Explicit Proxy Issue with FQDN Resolution to IPv6 (FortiOS 7.4.7)
- NetFlow vs PCAPIntroduction As networking professionals, we rely on tools like NetFlow and PCAP (packet capture) to monitor, troubleshoot, and secure our networks. While both provide critical insights, they serve distinct purposes: NetFlow offers summarized traffic metadata, while PCAP delivers raw, packet-level details. The Cisco Nexus 9000 series stands out with its ability to support unsampled NetFlow… Read more: NetFlow vs PCAP
- FortiGate Proxy Chain Issue with FQDN Resolution (FortiOS 7.4.7)I recently encountered an issue with the proxy chain function on a FortiGate 121G running FortiOS 7.4.7, and I wanted to share my findings in case others are facing similar problems. Issue Description:When configuring an upstream proxy using an FQDN in the proxy chain, the function intermittently fails. After extensive troubleshooting, including log retrieval and… Read more: FortiGate Proxy Chain Issue with FQDN Resolution (FortiOS 7.4.7)
- How it works of DPD (Dead peer detection) in ipsec VPN and TroubleshootingI’m troubleshooting an unstable IPsec VPN where one peer is behind NAT, using UDP 500/4500, with issues like random firewall packet drops (due to UDP flood protection) and bandwidth exceedance. Here’s a detailed breakdown of how Dead Peer Detection (DPD) works and how to address these issues. How Dead Peer Detection (DPD) Works DPD (RFC… Read more: How it works of DPD (Dead peer detection) in ipsec VPN and Troubleshooting
- The Verb “To Be” as the Root (Understand in 5 mins)The verb “to be” is like the heart of English grammar—it’s used everywhere to say who you are, how things are, or what will happen. You might have noticed that we say “I am a student” or “She is a doctor,” but NOT “I to be a student.” Why? Because “to be” is the root… Read more: The Verb “To Be” as the Root (Understand in 5 mins)