标签：#SEC

A lot of Linux incident response starts with a login question, not a malware sample. Someone sees a spike of failed SSH attempts. A root login appears in the wrong time window. A service account logs in from an address nobody recognizes. A helpdesk ticket says "the server looks weird" and the only concrete clue is a username or IP address. At that point, the useful question is not "is this host compromised?" It is more boring and more important: Did anyone actually authenticate? Which account was involved? Was it password, key, sudo, su, or a scheduled task? Was the same IP seen in web logs, current sockets, process context, or command history? Did persistence, services, packages, or recent files change near the same time? Can another responder review exactly what evidence was collected? That last point matters. If you let an AI assistant freely run shell commands during the first pass, you can get speed, but you also create a new risk: the model may over-collect, mutate the host, or produce a confident answer that nobody can audit later. For a login anomaly, I prefer a read-only evidence loop. A practical first pass Start with the narrow clue if you have one. If the alert names a user: oi login --user root -s 7d If the alert names an IP address: oi login --ip 203.0.113.44 -s 7d If the alert is vague, start wider: oi login -s 7d oi scan -s 7d The goal of the first pass is not to prove every detail. The goal is to build a timeline that a human responder can challenge. For a suspicious SSH login, I want the initial report to answer five things. 1. Authentication pattern Look for the difference between noise and access. A server can receive thousands of failed SSH attempts from the internet. That is useful background, but it is not the same as a successful session. The first split should be: failed attempts only successful login after many failures accepted key from an unusual source login by an account that normally should not be interactive root login where root SSH

The Transition A few years ago, bug hunting was a manual craft. You scanned subdomains with one tool, tested endpoints with another, and stitched results together by hand. Today, AI changes the speed entirely. Not by replacing the hunter. By eliminating the boring parts. What AI Actually Changes 1. Reconnaissance at Scale Subdomain enumeration, port scanning, and technology fingerprinting used to take hours. AI-powered pipelines now do this in minutes: Passive reconnaissance via Certificate Transparency logs, search engines, and DNS records Automated crawling and endpoint discovery Technology stack detection from response headers and HTML patterns JavaScript file analysis for hidden endpoints and API keys The machine does the grunt work. The human interprets the results. 2. Pattern Recognition Vulnerability classes have signatures. SQL injection looks different from XSS, which looks different from SSRF. AI models trained on thousands of real vulnerabilities can flag suspicious patterns faster than manual code review. This is not about finding zero-days. It is about catching the low-hanging fruit that everyone else misses because they are in a hurry. 3. Intelligent Fuzzing Traditional fuzzers throw random data at endpoints and wait for crashes. AI-guided fuzzers understand the input format and generate test cases that explore edge cases a human would not think of. The result: fewer requests, better coverage, higher signal-to-noise ratio. Where AI Struggles Business Logic Flaws AI does not understand your application's purpose. It cannot tell if a discount code is applied twice, or if a user can access another user's private data through a convoluted API flow. These are the vulnerabilities that require context. Human context. Authentication Logic Authentication bypasses are often creative. They exploit the gap between what the developer intended and what the code actually enforces. AI can find simple auth flaws, but multi-step authentication bypass chains still need h

Overview This is my first real-world cybersecurity VAPT experience inside an enterprise insurance company environment. I worked across network infrastructure, web applications, internal devices, and physical security — and learned how professional security assessments are actually performed beyond labs and CTFs. Introduction I am a cybersecurity enthusiast focused on SOC operations, web application penetration testing, and vulnerability assessment. In this engagement, I worked on assessing the security posture of an insurance company across its network infrastructure, devices, web applications, and physical security controls. This was my first real-world experience working in an enterprise environment, and initially I was not fully confident about the workflow. However, with the guidance and support of my senior, I was able to understand the process step by step and actively contribute to the assessment. Objective Identify security vulnerabilities across network, web, and internal systems Assess exposure of critical assets Analyze potential attack paths in the environment Evaluate basic physical security controls Scope of Work Network infrastructure assessment Web application security testing Device-level security review Basic physical security evaluation Tools Used Nessus (vulnerability scanning) Burp Suite (web application testing & request interception) Nmap (network discovery & port scanning) GVM / OpenVAS (vulnerability assessment) OWASP ZAP (automated web scanning) Wireshark (packet analysis & traffic inspection) Approach / Methodology Performed network discovery using Nmap to identify active hosts and open ports Conducted vulnerability scanning using Nessus and GVM to detect known security issues Analyzed web application behavior using Burp Suite and OWASP ZAP Intercepted and inspected HTTP/HTTPS traffic to understand request/response flow Used Wireshark to analyze packet-level communication and detect anomalies Evaluated system exposure across internal devic

"The output filter runs after the LLM has already seen the confidential data. By then, three classes of leak can no longer be stopped. The right surface is retrieval. Walking through a real implementation." TL;DR Most RAG-with-RBAC stacks I see in production put the access-control gate at the output stage: an LLM-response post-filter that masks PII or redacts confidential strings. This is defense-in-depth, not the load-bearing layer. By the time the filter runs, the LLM has already received the confidential context, and three classes of leak — creative paraphrasing, inference, cross-turn persistence — can no longer be stopped by string-matching the output. The protective surface that actually carries the weight is retrieval-stage ABAC: documents and graph nodes the user can't read are never traversed, never make it into the prompt, never seen by the model. The output filter still belongs in the stack, but as the second-to-last line, not the first. This post is a walk through why and how, with code references from a working implementation. It was prompted by a 6-turn LinkedIn DM exchange with Ali Afana (Provia founder, dev.to Featured) on injection-fixture schema design, where the framing crystallized. The seductive default You build a RAG system. You have documents at different sensitivity levels — public, internal, confidential. You want the model to answer based on whichever documents the user is allowed to see. The default mental model: "I'll let the model answer freely, and then I'll filter the response on the way out." This is appealing because: The retrieval pipeline stays simple (one query, one vector search, one response) The access control feels surgical (just before the user, just before damage) The PII-mask vocabulary is well-established (Presidio, regex catalogs, named-entity recognition models) So you wire up something like: Python The seductive default def answer(query, user): chunks = retrieve(query, top_k=10) # No ABAC here context = "\n".join(c.text

At a previous job I worked at as a Dev we had someone who ran Semgrep on our codebase for the first time. It came back with 180 findings. We had no security engineer. The developer who ran it looked at the output, closed the terminal, and we never ran it again. That's not a story about a careless team. That's a story about a tool that produced output most teams in small companies with no expertise knew what to do with. I've seen this exact moment happen more times than I can count working with small dev teams. And it's the reason I spent the last year building SecOpsium. But before I get to that let me explain the actual problem, because I think it's misunderstood. The problem isn't the scanning Semgrep and Gitleaks are excellent tools. They're free, actively maintained, and genuinely powerful. If you're not using them you should be. The problem is what happens 10 minutes after you run them. You get 200 findings. Some are critical. Some are test files. Some are commented-out code from 2021. Some are legitimate secrets. Some are variable names that pattern match against a rule but contain nothing sensitive. They all look the same in the output. Now you're a developer who also does DevOps, also reviews PRs, also handles incidents, and you're staring at 200 items with no clear indication of which three actually matter this week. So you close the terminal. Or you create a Jira ticket labeled "security findings" that lives in the backlog forever. Or you spend two days triaging manually and burn out before you fix anything. This is the real problem. The scanning was never the hard part. Why rule based scanners produce so much noise It helps to understand technically why this happens. Semgrep and Gitleaks are rule-based. They match patterns. A variable named api_key_example in a test file flags the same way as a live Stripe key in an active production config. Gitleaks scans for entropy and known credential patterns but can't distinguish between a key that was rotated and r

I had a screenshot to send. Nothing secret — a stack trace from a side project — but it had an internal hostname, a file path with my username, and a chunk of a config file in the terminal behind it. The fast move is to drag it onto a free image host and paste the link. I sat there with my cursor over the upload button and couldn't do it. Because I know what happens next. That image lives on someone else's infrastructure, indefinitely, behind a URL I don't control, and I have no idea who else can reach it. For a throwaway screenshot, that's a permanent record I never agreed to. So I closed the tab and built a thing instead. It's called tmpdrop , and it's ~500 lines of Node. The threat model The problem with public file hosts isn't that they're evil. It's the gap between what you intend ("share this once, with one person") and what the platform delivers ("store this forever, serve it to anyone who finds the link"). A few specific things go wrong: Retention. "Temporary" hosts keep your files long after you've forgotten them. There's no expiry you can trust, and deletion is usually best-effort. Predictable URLs. Plenty of hosts use sequential or short IDs. Scrapers walk the keyspace and hoover up everything. Your "private" link was never private. Stored XSS via uploads. If a host serves an uploaded .html or .svg file inline with a permissive content type, an attacker can ship JavaScript that runs in your browser, in the host's origin. Your file host becomes an XSS delivery service. Abuse vectors. No rate limit means the box is a free CDN for whatever someone wants to dump on it — malware, spam payloads, the works. So the design goal wasn't "another uploader." It was: close each of those gaps, then stop. What I built tmpdrop is a single Fastify server backed by SQLite. The whole defensive surface is small enough to hold in your head: Unguessable URLs. Slugs are 9 random bytes, base64url-encoded — 72 bits of entropy. You cannot enumerate them. A TTL reaper. Every upload

🗓️ This Week Completed two more sections of the SwiftUI tutorial 🦾 As I continue working through the tutorial, I can feel my understanding of SwiftUI fundamentals becoming more solid 🔥 It was my first time posting a standalone article about reverse engineering📝 If you're interested, feel free to check it out 👇 A Curious Journey Into Reverse Engineering an AI-Generated Python .exe Umitomo Umitomo Umitomo Follow May 26 A Curious Journey Into Reverse Engineering an AI-Generated Python .exe # beginners # reversing # security # python 5 reactions Comments Add Comment 5 min read I started creating UI designs for my future portfolio website in Figma. I was able to roughly sketch out the overall structure of the site, but I also realized how difficult it is to create modern and stylish UI designs. (It really made me realize I don’t have much design sense yet 😂💦) While struggling with the design process, I came across several articles about Figma MCP . That made me interested in exploring how generative AI could help with UI design ideas, so I decided to start researching Figma MCP further. Completed Securing AI Systems room from the AI Security Learning Path on TryHackMe this week🤖 📱 iOS (SwiftUI) Worked through the SwiftUI tutorial and completed "Create an Algorithm for Badges" and "Add inclusive features" 🌐 Web Development Posted my weekly dev log on Dev.to and a standalone article about my first attempt at reverse engineering 📝 Created rough portfolio website UI layouts in Figma Used shadcn/ui component library design templates in Figma Started learning UI design in Figma using community resources 🔐 Security (TryHackMe) Completed Securing AI Systems room (part of the AI Security Learning Path) on TryHackMe. 💡 Key Takeaways 📱 SwiftUI Learning Add inclusive features Learned that SwiftUI automatically adapts UI elements for Light and Dark Mode by default. Learned how to preview and compare Light and Dark Mode layouts in the Xcode canvas. Understood that system-provided sema

GHES Key Rotation, Bug Bounty Program Refocus, AI Agent Permission Fatigue Today's Highlights This week's top security news features critical action for GitHub Enterprise Server users with a signing key rotation due to an ongoing investigation. We also cover GitHub's strategic refocusing of its bug bounty program for higher quality submissions and an interactive look at AI agent permission fatigue. Investigation update: GitHub Enterprise Server signing key rotation (GitHub Blog) Source: https://github.blog/security/investigating-unauthorized-access-to-githubs-internal-repositories/ This alert details a critical security update for GitHub Enterprise Server (GHES) customers, urging immediate action to rotate signing keys. The blog post indicates an investigation into unauthorized access to GitHub's internal repositories, which has necessitated this widespread security measure. While specific details of the breach or vulnerability are not fully disclosed, the requirement for a signing key rotation points to a potential compromise of cryptographic keys, which are fundamental to authentication and supply chain integrity. Such incidents could lead to unauthorized code signing, repository tampering, or other severe supply chain attacks, underscoring the importance of robust secrets management and incident response protocols. The advisory emphasizes a proactive stance for GHES administrators to protect their environments by following the provided guidance. This incident highlights the pervasive risk of supply chain attacks and the critical role of secure key management in enterprise environments. It reminds organizations that even trusted platforms like GitHub are targets and necessitates vigilant monitoring and swift action in response to security advisories. The prompt action from GitHub, though implying a significant security event, also showcases their commitment to transparency and securing their ecosystem by guiding customers through the necessary remediation steps to

Undisclosed addition in jqwik instructed AI coding agents to delete app output.

A new hacking campaign is trying to trick Signal users to give up their secret recovery key, which can be used to access online backups containing past messages.

Pay Tel secured the publicly exposed data after security researchers discovered the leak containing callers' sensitive ID documents and inmate communications.

The US military has long known that cheap fixes could stop location data from exposing its troops. It adopted almost none—and now says adversaries are using the data to target soldiers during a war.

One leading privacy lawmaker said it was time to "start treating the adtech industry as a national security threat."

One poisoned extension, one package install, one CI workflow. Any of them can now be the first domino. That is the uncomfortable lesson from the latest Shai-Hulud activity and GitHub’s recently confirmed internal-repository breach. The scary part is not only the number of affected packages, tokens, or repositories. Counts move fast. The scarier part is where the attacker code ran: inside the trusted developer and CI path. The modern supply chain is not just “the dependencies we ship to production.” It is your IDE, your package manager, your GitHub Actions runner, your cache keys, your OIDC flow, your local gh auth, your AI coding tool config, and the cloud account that quietly pays the bill when something goes sideways. What happened, briefly CISA described the original Shai-Hulud wave as a self-replicating npm worm that compromised more than 500 packages and targeted GitHub personal access tokens plus AWS, GCP, and Azure keys. GitHub later said it removed 500+ compromised packages and began pushing npm toward shorter-lived credentials, 2FA enforcement, and trusted publishing. The later waves got more CI-aware. Instead of only stealing npm tokens from maintainers, they looked for credentials inside build environments, abused publishing workflows, and used the build system itself as distribution. Microsoft’s May 2026 reporting on the @antv ecosystem described a “Mini Shai-Hulud” style campaign that targeted GitHub Actions environments and stole GitHub, AWS, Vault, npm, Kubernetes, and 1Password secrets. Microsoft said GitHub removed 640 malicious packages and invalidated 61,274 npm granular access tokens with write permissions and 2FA bypass. Then GitHub confirmed an incident involving a compromised employee device and a poisoned third-party VS Code extension. GitHub said the attacker’s claim of roughly 3,800 internal repositories was “directionally consistent” with its investigation, while also saying its current assessment was exfiltration of GitHub-internal reposi

Threat-intel reports from recent years document campaigns in which attackers obtain AWS IAM credentials from developer workstations, use them to enumerate cloud accounts and access Kubernetes clusters. From there, attackers deploy poisoned container images to move laterally and harvest secrets. The MITRE ATT&CK chain maps to: T1552.001 ( Credentials in Files ) → T1078.004 ( Valid Accounts: Cloud Accounts ) → T1610 ( Deploy Container ) → T1496 ( Resource Hijacking ). This is not an isolated case. The Shai-Hulud supply chain attack harvested Kubernetes credentials from CI and developer workstations, feeding exactly this kind of attack chain. This research started with a short list of questions: What are Kubernetes secrets, exactly? What can an attacker do with them? How can defenders harden their clusters? So before we look at what we found in the wild, and how to harden clusters to mitigate impacts, let's define what Kubernetes secrets are. Three Surfaces, Three Secret Formats A simplified view of the cluster has three sides that matter for this post: A developer, or automation pipeline, talks to the Kubernetes API server with credentials. That is the canonical front door. On every node, the kubelet exposes its own HTTPS API. The same credentials can authenticate to it directly when it is reachable on the network. The cluster's nodes pull images from container registries (Docker Hub, GitHub Container Registry, ECR, Quay, GitLab, ACR…) using a second set of credentials. Kubernetes Architecture These are the attack surfaces where leaked secrets have the most impact, and three secret formats unlock them: TLS client certificates are used by humans through a kubeconfig file with the kubectl command to connect to a Kubernetes cluster. JSON Web Tokens, or Service Accounts, are non-human identities (NHI) used to automate cluster operations from CI/CD jobs, controllers, and integrations. By default, JWTs have no expiration date — which is why a JWT leaked years ago can still

Google Home is rolling out a new Gemini-powered automation feature that can trigger smart home routines based on what your security cameras can see. This is one of several updates announced yesterday for Gemini for Home, including enhanced voice command support and general stability improvements, following its early access launch in October. "We are introducing […]

Customer data from more than 350 hotels around the world may have been accessed as part of realistic reservation-hijacking scams.

Demystifying WebP to PNG: How to Secure Serverless Edge Routing Configurations Safely We have all been there. You are building a high-performance, modern web application and you decide to store all user-generated assets in modern, ultra-compressed WebP formats. It is a smart move for your Google Lighthouse scores. Then, the legacy enterprise integration request hits your inbox. A major client needs to pull these same assets dynamically, but their internal 15-year-old reporting engine only supports PNG. Suddenly, you need to configure a runtime conversion pipeline that handles complex input schemas, transforms formats on the fly, and manages edge routes without exposing your internal database claims or API secrets. Setting up secure serverless edge routing configurations to convert images on-demand can quickly turn into a security nightmare. If you do not handle incoming credential tokens correctly, you risk forwarding sensitive OAuth scopes or database keys directly to downstream image-processing worker nodes. In this guide, we will break down exactly how to architect a lightweight, secure, and fast edge routing pipeline that validates incoming image request schemas and converts WebP to PNG without leaking sensitive backend credentials. The Problem Modern edge runtimes like Cloudflare Workers, Vercel Edge Functions, or AWS CloudFront Functions are incredibly fast, but they have strict execution limits. They run on V8 isolates, meaning you do not have a full Node.js environment with unlimited memory and access to heavy C++ binaries like sharp or canvas without paying a massive cold-start penalty. If you want to support legacy clients by converting WebP to PNG on the fly, you are faced with three major challenges: Bundle Size Restrictions : Edge functions typically restrict your code size to 1MB or 2MB. Bundling heavy native libraries to parse image bytes is a recipe for deployment failures. Credential Leakage : Edge routers often intercept incoming JWT authorization

That "authenticity of host can't be established" message isn't just noise. Here's what's actually happening — and why blindly typing "yes" is a security mistake. Every developer has seen this: The authenticity of host 'example.com (203.0.113.1)' can't be established. ED25519 key fingerprint is SHA256:abc123xyz... Are you sure you want to continue connecting (yes/no/[fingerprint])? Almost everyone types yes without reading it. Then they move on. This message is SSH trying to protect you from one of the most dangerous attacks in network security: the man-in-the-middle attack. Understanding what's happening here — and what the ~/.ssh/known_hosts file actually does — will change how you think about every SSH connection you make. The Problem SSH Is Solving When you connect to ssh user@example.com , how do you know you're actually talking to example.com ? You can't rely on the IP address — IP addresses can be spoofed or rerouted. You can't rely on DNS — DNS can be poisoned. You can't rely on the network path — traffic can be intercepted at any point between you and the server. Without verification, an attacker positioned between you and the server could intercept the connection, pose as the server, decrypt everything you send, re-encrypt it, and forward it along. You'd type your password or authenticate with your key and never know the attacker saw every keystroke. This is a man-in-the-middle (MITM) attack . It's not theoretical. It happens on compromised networks, corporate proxies, malicious Wi-Fi hotspots, and misconfigured infrastructure. SSH's defense is host key verification . Every SSH server has a unique cryptographic identity — its host key. Before you exchange any sensitive data, the server proves it holds the private key corresponding to a public key you've previously verified. If the keys don't match, SSH warns you — loudly. What a Host Key Actually Is When OpenSSH is installed on a server, it automatically generates a set of host key pairs. These live in /etc

⚠️ For defensive/educational purposes only. Sniff only networks you own or are explicitly authorized to test. Unauthorized network monitoring is illegal in most jurisdictions. The uncomfortable truth about your factory floor If your plant uses Modbus TCP — and statistically, it probably does — every register read, every coil write, every sensor value is flying across your network in plaintext . No encryption. No authentication. No signature. Nothing. Modbus was designed in 1979 by Modicon for serial communication between a PLC and a few field devices on a dedicated cable. The threat model was "someone might physically tap the wire." The solution was "don't let strangers into the control room." Forty-five years later, that same protocol is running over your corporate VLAN, talking to cloud historians, and occasionally — if your IT/OT segmentation has gaps — reachable from the internet. Let me show you what that looks like from the wire. The 5-line sniffer This is a defensive monitoring tool. Same code your blue team would use to baseline normal traffic and detect anomalies. Requires scapy : pip install scapy from scapy.all import sniff , TCP , Raw def show_modbus ( pkt ): if TCP in pkt and pkt [ TCP ]. dport == 502 and Raw in pkt : payload = pkt [ Raw ]. load print ( f " { pkt [ ' IP ' ]. src } → { pkt [ ' IP ' ]. dst } : { payload . hex () } " ) sniff ( filter = " tcp port 502 " , prn = show_modbus , store = False ) Run it on a span port, a TAP, or a mirror VLAN, and within seconds you'll see something like this: 192.168.1.50 → 192.168.1.10: 0001000000060103006400 02 192.168.1.10 → 192.168.1.50: 00010000000701030441f00000 192.168.1.50 → 192.168.1.10: 00020000000601100065000102 Every byte tells a story. Let's decode the first packet. Decoding what you just captured The Modbus TCP frame format is documented in the spec (it's public — that's part of the problem): Bytes 0-1: Transaction ID Bytes 2-3: Protocol ID (always 0x0000 for Modbus) Bytes 4-5: Length Byte 6: Unit