Developers, be cautious out there! Last year, I had my first encounter with a job scam. Someone reached out to me on Fiverr, claiming they needed help fixing a full-stack application due to issues like lag and loading problems. They started with a big budget and emphasized urgency, saying they wanted the work done quickly. Their constant insistence raised my suspicion: "Get the code running on your machine and show the application working. Then I'll consider you for the role." I decided to check the codebase on GitHub. It was a MERN stack application, and I thought to myself, "Easy peasy!" I cloned the repository and was about to run npm install. Then, I paused. Something didn’t feel right, so I took a closer look at the package.json file and the project files. That’s when I noticed SQL dependencies in the package.json. 🚩 At that point, I aborted the mission and blocked the person. They kept pestering me, asking if I had a working web app running on my machine. This was the first of several similar experiences. Unfortunately, scams like this are becoming more common, especially in the freelancing world. Here are some red flags to watch out for: 1. Requests to "attach a screenshot of the running app" to your offer. 2. Suspiciously high budgets paired with unrealistic deadlines. 3. Pushy behaviour, insisting you run the code before getting hired. Another common scam: Recruiters reaching out on LinkedIn, offering a role. They’ll provide you with a codebase as part of a "technical exercise" and ask you to run the code on your machine. My advice: Always check project files thoroughly, especially the package.json file. If something seems off, trust your instincts and walk away. Update: I may not have the right words to explain my experience, but thanks to the amazing comments I’ve received, I want to share this additional insight. The first time I encountered this, I installed the application. That’s when the software started requesting unusual permissions on my computer, all through VS Code: 1. VS Code want to access your files. 2. VS Code want to access your contacts. I’ve been using VS Code for a long time, and I haven’t recently reinstalled it. Besides, why would VS Code ever need access to my contacts? That’s when I realized it wasn’t VS Code—it was likely a program trying to gain unauthorized access to my computer. If you’ve experienced something similar or can explain this better, please share your thoughts in the comments. Let’s help keep our community safe by sharing this post to spread awareness. Together, we can protect developers from falling victim to these scams. Stay safe out there!
Email Security Concerns
Explore top LinkedIn content from expert professionals.
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Case Study. Must read. Fixing Gmail deliverability isn’t as simple as changing your IP or switching platforms. In one real case: A brand moved to a dedicated IP on their ESP’s advice, hoping it would fix domain reputation issues. Warm-up was done correctly. SPF, DKIM, and DMARC were all passing. But Gmail Postmaster reputation dropped to "bad" and stayed there Gmail inbox placement went to 0%. CTRs were around 0.2%, and nothing improved. The core issue wasn't technical. It was behavioral. Their student emails were opt-in. But corporate emails came from purchased ZoomInfo lists. Gmail picked up on this and punished the entire domain. Changing IPs just exposed the issue faster. Their suppression logic also made things worse: 1. Users were suppressed only after 10 sends with no clicks 2. That means 10 chances to hurt domain reputation 3. Engagement-based filtering is strict 4. If people don’t interact, Gmail assumes your content is unwanted Technical setup wasn't perfect either: 1. Their signup API lacked rate limits 2. Bots were likely abusing the form 3. This led to emails being sent to fake or unverified addresses More bad signals sent to Gmail A "0% spam complaint rate" looked good on paper, but it was misleading. If no one sees your email in the inbox, they can’t complain. That’s a sign your emails are already deep in spam. Should you ever change IPs? Yes, if recommended by an experienced deliverability expert because the IPs are burnt and beyond recovery anytime soon. But only after identifying and fixing the root cause. Changing IPs without fixing your behavior is just a temporary patch What can actually help? Along with all other best practices, 1. Stop mailing Gmail users for a while. 2. Start fresh with small, high-quality segments. 3. Promote your email content on your website or social media to drive awareness. Good deliverability doesn’t come from tools or IPs. It comes from permission, relevance, and engagement. I have seen a lot of marketers with no optin lists but with content relevance and positive engagement they are doing great. If Gmail doesn’t see real interest in your emails, nothing else will matter. Happy to chat if you're navigating a similar situation. #email #emailmarketing
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Headline: China Cracks RSA Encryption Using Quantum Annealing—Global Data Security Now Under Pressure ⸻ Introduction: A Chinese research team has achieved a milestone with profound cybersecurity implications: successfully cracking a small RSA-encrypted integer using a quantum computer. Though modest in scale, this experiment signals that quantum systems are starting to undermine the very cryptographic foundations that secure today’s banking, commerce, and communication systems. The race to build quantum-resistant encryption is no longer theoretical—it’s urgent. ⸻ Key Details 🔓 Cracking RSA with Quantum Annealing • Researchers: Wang Chao and team from Shanghai University. • Hardware Used: A D-Wave Advantage quantum annealer, built by D-Wave Systems. • Achievement: The team factored a 22-bit RSA semiprime integer, a task previously unsolved on this class of hardware. 🔐 What Makes RSA Strong—and Vulnerable • RSA Encryption: Based on the difficulty of factoring large semiprime numbers (products of two primes). • Classical Challenge: Conventional computers require subexponential time to factor 2048-bit keys—considered secure for now. • Largest Cracked Classically: RSA250 (829-bit key) using supercomputers over weeks. • Quantum Approach: The Chinese team translated factorization into a QUBO (Quadratic Unconstrained Binary Optimization) problem, solvable by quantum annealing. 🧠 Why This is a Warning Shot • Early Stage, But Symbolic: While a 22-bit number is trivial by today’s standards, the methodology proves scalability potential. • First Step Toward Quantum Decryption: Demonstrates quantum annealers can be adapted for cryptographic tasks—not just optimization. • Signals Future Risk: Today’s encryption might withstand current tech, but scalable quantum systems could break RSA entirely in years, not decades. ⸻ Why It Matters • Global Cybersecurity Threatened: Banking, defense, healthcare, and internet infrastructure all rely on RSA and similar public-key systems. This experiment shows those systems may soon be obsolete. • Quantum Arms Race Accelerates: The demonstration by Chinese researchers will likely intensify global investment in both quantum computing and post-quantum cryptography. • Urgent Need for Migration: Governments and corporations must begin transitioning to quantum-resistant encryption standards, or risk catastrophic breaches in the near future. • Tactical and Strategic Implications: Countries that master quantum decryption first may gain unparalleled capabilities in espionage, warfare, and economic control. ⸻ Keith King https://lnkd.in/gHPvUttw Arzan Alghanmi
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Google is issuing a call to action: the quantum era will break the digital locks we rely on, and the window to get ahead of it is closing rapidly. This is a signal leaders should not ignore. Quantum’s promise, drug discovery, materials science, energy, comes with a brutal side effect: a cryptographically relevant quantum computer could unravel the public-key cryptosystems protecting bank transfers, private chats, trade secrets, and classified systems. And the most dangerous part is timing. Attackers don’t need quantum to arrive to start winning. They can harvest encrypted data now and decrypt it later. The breach happens in slow motion, then shows up all at once, helped by AI to find patterns and insights in the data. I’ve been saying this for years: if the last few years belonged to AI, the rest of this decade increasingly belongs to quantum, and the world is not ready for quantum’s “ChatGPT moment.” Standards are no longer the excuse. National Institute of Standards and Technology (NIST) finalized the first post-quantum cryptography standards in August 2024. This is the most underpriced risk in modern leadership. The “we’re waiting” era is over. Y2K was a $100B inconvenience. Quantum migration is a civil-engineering project for the digital world. Imagine a an airplane swapping engines mid-flight without crashing. That’s what “crypto agility” demands: replacing the cryptography under your entire business while customers keep booking, checking-in, boarding, and trusting the system. And the time to start working is today, because when one of the companies building toward this future tells the market to move, you move. Google has been working on post-quantum cryptography since 2016, and it’s now publicly warning that a large-scale quantum computer could break today’s public-key cryptography. That combination, deep capability plus an explicit call to action, isn’t PR. It’s a timeline a signal you should not ignore. This decade rewards leaders who modernize trust before trust collapses. Is your organization preparing itself for what is to come?
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The biggest threat to your data isn’t happening tomorrow. It happened yesterday. If you haven’t heard of HNDL (Harvest Now, Decrypt Later), your long-term data strategy has a massive blind spot. Here is the reality: State actors and cybercriminals are capturing your encrypted data today. They can’t read it yet, so they’re storing it in massive data vaults, waiting for the "Qday"—the moment quantum computers become powerful enough to break current encryption. If your data needs to stay private for 5, 10, or 20 years, it’s already at risk. What’s on the line? ↳ Intellectual Property (IP) and trade secrets. ↳ Government and identity data. ↳ Long-term financial records and contracts. ↳ Sensitive customer health data. How do we solve it? 🛠️ We cannot wait for quantum supremacy to react. The fix starts now: ↳ Inventory: Identify which data has a long shelf-life. ↳ Crypto-Agility: Move toward systems that can swap encryption methods without a total overhaul. ↳ Hybrid PQC: Implement Post-Quantum Cryptography alongside classical methods to ensure traffic captured today remains a mystery tomorrow. The transition to quantum-resistant security is a marathon, not a sprint. Are you tracking HNDL on your current risk register? Let’s discuss in the comments. 👇 P.S. If you want help mapping your exposure or building a PQC migration plan, drop me a message. ♻️ Share this post if it speaks to you, and follow me for more. #QuantumSecurity #PQC
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🔍Deep Dive into SMTP Port Penetration Testing: Advanced Techniques for Cybersecurity Professionals🔍 As cybersecurity professionals, we know that securing email communications is paramount. One of the critical protocols in this space is SMTP (Simple Mail Transfer Protocol). In this post, I want to share some advanced techniques for performing effective SMTP port penetration testing. Why Focus on SMTP? SMTP is the backbone of email communication, and vulnerabilities in this protocol can lead to significant security breaches, such as: - Email Spoofing: Attackers impersonating legitimate users. - Data Leakage: Unauthorized access to sensitive email content. - Denial of Service (DoS): Overloading mail servers to disrupt communication. Techniques for SMTP Port Penetration Testing 1. Port Scanning and Enumeration: - Use tools like **Nmap** to identify open SMTP ports (commonly 25, 587, 465). - Employ scripting to automate enumeration of service versions and supported commands. 2. Service Version Detection: - Utilize Nmap scripts or tools like SMTP-USER-ENUM to identify potential users and misconfigurations. - Check for outdated versions of SMTP servers which might be susceptible to known exploits. 3. Command Injection Testing: - Test for command injection vulnerabilities using carefully crafted payloads. For example, manipulating SMTP commands like `MAIL FROM`, `RCPT TO`, and `DATA` to perform actions such as revealing user information. 4. Exploiting Misconfigurations: - Look for open relays, which allow unauthorized users to send emails through the server. This can lead to spam and phishing attacks. - Check for improper authentication mechanisms that can be bypassed, leading to unauthorized access. 5. Utilizing Advanced Tools: - Metasploit: Use modules like `auxiliary/scanner/smtp/smtp_enum` for user enumeration and `auxiliary/scanner/smtp/smtp_login` for brute-forcing authentication. - Burp Suite: Analyze SMTP traffic in-depth, manipulate requests, and identify vulnerabilities in web applications that interface with email services. 6. Brute Force and Dictionary Attacks: - Test the robustness of SMTP authentication by performing dictionary attacks on login credentials. Ensure to have explicit permission to avoid legal repercussions. 7. Analyzing SMTP Traffic: - Use Wireshark or similar tools to capture and analyze SMTP traffic. Look for unencrypted sensitive information and ensure that STARTTLS is enforced where applicable. Best Practices Post-Testing - Always report findings in a clear, actionable format. - Collaborate with development and operations teams to remediate vulnerabilities. - Implement continuous monitoring and regular audits of SMTP configurations. Let’s share knowledge and best practices to strengthen our defenses against email-based threats! 💡 #Cybersecurity #PenetrationTesting #SMTP #EmailSecurity #NetworkSecurity #Infosec #CyberAwareness #RedTeam #BugBounty #Ports #Protocols
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SMTP Penetration Testing – Securing Your Email Infrastructure 📧🔐 Email security is more critical than ever. 🚨 With phishing, email spoofing, and SMTP relay abuse on the rise, organizations need to proactively test and secure their SMTP servers to prevent cyber threats. The “SMTP Penetration Testing Research Report” provides a comprehensive guide on testing and securing SMTP servers against brute-force attacks, user enumeration, email spoofing, and open relay exploits. ----- 🚨 Why SMTP Security Matters SMTP was not originally designed with security in mind, making it vulnerable to: 🔹 Open Relay Abuse – Attackers send spam or phishing emails using your server. 🔹 User Enumeration – Exploiting SMTP commands (VRFY, EXPN, RCPT TO) to harvest valid email addresses. 🔹 Brute-Force Attacks – Cracking weak credentials to gain unauthorized access. 🔹 Lack of Encryption – Without TLS, emails are transmitted in plain text, making them easy to intercept. ----- 🕵️♂️ SMTP Penetration Testing Techniques ✅ Banner Grabbing – Identify SMTP server version & vulnerabilities using: • telnet <target_IP> 25 • nmap -sV -p 25 <target_IP> ✅ User Enumeration – Find valid email addresses using: • VRFY admin@example.com • EXPN mailinglist@example.com • Nmap & Metasploit SMTP Enumeration Modules ✅ Brute Force Attacks – Crack weak credentials using: • hydra -l user -P passwords.txt smtp://<target_IP> • medusa -h <target_IP> -u user -P passwords.txt -M smtp ✅ SMTP Relay Attacks – Test for open relays with: • nmap -p 25 --script smtp-open-relay <target_IP> ----- 🔐 How to Secure Your SMTP Server 🔹 Disable Open Relays – Require authentication for sending emails. 🔹 Implement TLS Encryption – Use STARTTLS to encrypt email traffic. 🔹 Restrict SMTP Commands – Disable VRFY & EXPN to prevent user enumeration. 🔹 Enable SPF, DKIM, and DMARC – Prevent email spoofing & phishing. 🔹 Monitor SMTP Logs – Detect brute force attempts, unauthorized access, and spam activity. ----- 🚀 Real-World Case Study: Fixing an SMTP Security Breach 🔴 Issue: An organization’s SMTP server was an open relay, leading to spam abuse, phishing, and IP blacklisting. ✅ Solution: ✔️ Disabled open relay functionality. ✔️ Implemented SPF, DKIM, and DMARC for authentication. ✔️ Enforced TLS encryption for secure communication. ✔️ Monitored SMTP logs & access controls. ⚡ Result: Spam was eliminated, phishing attacks decreased, and email deliverability improved. ----- 🔎 Take Action: Test Your SMTP Security Email security is not just about spam filters—your SMTP server can be a major attack surface. Have you tested yours? #CyberSecurity #EmailSecurity #SMTP #PenTesting #PhishingPrevention #RedTeam #InfoSec #PenetrationTesting #EthicalHacking
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Three weeks ago, our Devsinc security architect, walked into my office with a chilling demonstration. Using quantum simulation software, she showed how RSA-2048 encryption – the same standard protecting billions of transactions daily – could theoretically be cracked in just 24 hours by a sufficiently powerful quantum computer. What took her classical computer billions of years to attempt, quantum algorithms could solve before tomorrow's sunrise. That moment crystallized a truth I've been grappling with: we're not just approaching a technological evolution; we're racing toward a cryptographic apocalypse. The quantum computing market tells a story of inevitable disruption, surging from $1.44 billion in 2025 to an expected $16.22 billion by 2034 – a staggering 30.88% CAGR that signals more than market enthusiasm. Research shows a 17-34% probability that cryptographically relevant quantum computers will exist by 2034, climbing to 79% by 2044. But here's what keeps me awake at night: adversaries are already employing "harvest now, decrypt later" strategies, collecting our encrypted data today to unlock tomorrow. For my fellow CTOs and CIOs: the U.S. National Security Memorandum 10 mandates full migration to post-quantum cryptography by 2035, with some agencies required to transition by 2030. This isn't optional. Ninety-five percent of cybersecurity experts rate quantum's threat to current systems as "very high," yet only 25% of organizations are actively addressing this in their risk management strategies. To the brilliant minds entering our industry: this represents the greatest cybersecurity challenge and opportunity of our generation. While quantum computing promises revolutionary advances in drug discovery, optimization, and AI, it simultaneously threatens the cryptographic foundation of our digital world. The demand for quantum-safe solutions will create entirely new career paths and industries. What moves me most is the democratizing potential of this challenge. Whether you're building solutions in Silicon Valley or Lahore, the quantum threat affects us all equally – and so does the opportunity to solve it. Post-quantum cryptography isn't just about surviving disruption; it's about architecting the secure digital infrastructure that will power humanity's next chapter. The countdown has begun. The question isn't whether quantum will break our current security – it's whether we'll be ready when it does.
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I thought great copy was the secret to cold email. Then I realized 80% of my emails were landing in spam. Here’s what we found: 1️⃣ Domain protection is the #1 lever for deliverability → Most teams burn their main domain without realising it. Once a domain is flagged, everything gets filtered (even normal emails). We run 100+ secondary domains to protect our brand and reduce risk. Tool stack: Google Workspace, Namecheap, Warmup tools Next step: Move every outbound sequence off your primary domain. 2️⃣ Safe volume beats high volume → Sending 500 emails/day from one domain is the fastest path to spam. Deliverability collapses instantly. We spread volume across hundreds of mailboxes and stay under 40/day for each. Impact: Fewer red flags, higher trust, better inbox placement. Next step: Audit how many sends each domain is doing right now. 3️⃣ Authentication is non-negotiable → SPF, DKIM, and DMARC are the foundation ESPs check before letting anything through. Without proper authentication, you look suspicious by default. Tools: dmarcian, Google Admin, Cloudflare Next step: Run a deliverability test and fix whatever shows up in red. 4️⃣ Warm-up → Most domains get burned because people start sending too early. ESPs need time to trust you. We warm each domain for two full weeks before sending anything. Why it works: Slow ramp-up = better deliverability. If you just bought a domain, don’t touch it for 14 days. 5️⃣ Natural variation reduces spam triggers → Sending the same message repeatedly creates patterns that ESPs flag. You need micro-variation to look human. We use subtle spintax + a few message versions per campaign. Tools: Instantly.ai, Smartlead Next step: Add small variations to your first lines and CTAs. 6️⃣ Clean tracking protects your domain reputation → Tracking links are an instant red flag. Most agencies don’t realize this. We use custom tracking domains or disable tracking entirely for key campaigns. Next step: Replace all generic tracking links. The results: → 500,000+ emails/month reaching real decision-makers → Higher inbox placement across every ESP → Predictable revenue for ColdIQ clients → Stable domain health across all mailboxes Deliverability isn’t the flashy part of outbound, but it’s the part everything else depends on. If you want our 7-day GTM deliverability setup (domains, warm-up, templates, monitoring tools)... drop me a message, happy to help.