~/Rev_

Writeups

Research writeups, CVE→PoC breakdowns, box walkthroughs and notes from the field.

all#AI Lab#RTFM#CyberDen
2026-10-12A GPU Local-AI Lab on an External NTFS SSD (Docker on a Sparse ext4 Image)Containers and models on an external drive without reformatting it: Docker's data root inside a sparse ext4 image, GPU in containers, measured tokens/sec.#AI LabBuilt2026-09-16A Stable Fedora Checkpoint on a Hybrid-GPU LaptopTwo concrete faults behind a slow shutdown and a vanishing monitor (an NVIDIA daemon and a stale display layout), fixed and frozen at a known-good kernel.Stable checkpoint2026-09-12Building a Red-Team Field Manual From ATT&CK, Atomic Red Team and LOLBASA layered script pipeline that generates an Obsidian knowledge graph of tradecraft, rebuilt from scratch after an OS migration to prove it's reproducible.#RTFMBuilt, gaps listed2026-08-30Importing VulnHub OVAs and VMDKs into ProxmoxThe import workflow for pre-built vulnerable machines: extract, import the disk, match the virtual hardware to the guest's era, isolate on the attack segment.#CyberDenDone2026-08-10Jenkins on k3s With Persistent StateHelm said deployed, the pod said Init:CrashLoopBackOff. Reading the init container's logs found a volume-ownership issue; Jenkins now survives reboots.#CyberDenDone2026-08-02PowerEdge T320 Storage: PERC-Backed Bays and SMART TriageWhy AHCI doesn't expose the T320's front bays, how CyberDen's storage is laid out, and a checklist for triaging a SMART alert on a hypervisor SSD.#CyberDenNotes · short2026-07-26Memory-Safety Bug Classes in C: Indicator, Why, FixEach bug class reduced to the smallest snippet where it shows: why it's exploitable and the minimal fix. Built while learning fuzzing.medium2026-07-14PortSwigger SQLi: WHERE-Clause Injection and the Burp Workflow Behind ItWhat each part of the payload does, the Intercept-vs-Repeater mistake that hid a correct payload, and why Burp Community is enough.short2026-05-17OverTheWire Bandit: The Linux Fundamental Behind Each LevelNotes on what each level is really testing (paths, special filenames, dotfiles), plus a tmux workflow. No passwords.Series (add levels as you go) · short2026-05-03GTX 1070 Passthrough on a PowerEdge T320: A GPU Node for Local AIChoosing a card a tower server can power, validating it on the host, then binding it to VFIO and handing it to a dedicated inference VM.#CyberDen#AI LabDone2026-04-28NO-CARRIER on a Good Cable: Fixing Link AutonegotiationReading interface flags before touching config: a NIC and switch that couldn't agree on speed, and the ethtool fix.#CyberDenDone · short2026-03-14Design: A Homelab Log-Offload Pipeline With Write-Never-Read StorageFluent Bit to TrueNAS with per-source datasets and retention, enforced so a compromised VM can add logs but never erase them.#CyberDenDesign (partly built)2026-03-02One DNS Authority for a Segmented Lab, With Room Left for Red-Team TestingPi-hole as the resolver for every infrastructure segment, rolled out top-down, with three gotchas solved and offensive segments deliberately exempt.#CyberDenDone2026-02-03OpenCTI Restart Loop: The Admin Token Must Be a UUIDA fresh Docker Compose deploy that kept restarting, solved by one log line and a uuidgen.#CyberDenDone · short2026-01-20"This Switch Only Does 8 VLANs": The Myth That Cost Me a NetgearA UI limit mistaken for a forwarding limit, a switch bought and returned within a week, and why measuring beats buying.#CyberDenResolved · short2026-01-18Design: Routed Management vs a Bastion HostWhy routed management through the core router beat a dedicated bastion VLAN in a single-admin lab, and when a bastion comes back.#CyberDenDecision record · short2026-01-18The 60-Second SSH Drop, Part 3: Asymmetric Routing Through a Stateful FirewallRoot cause: pfSense saw only half of every management session. One route on the admin workstation fixed it at Layer 3, and the bastion VLAN came out.#CyberDenResolved · Series 3 of 32026-01-15The 60-Second SSH Drop, Part 2: Ruling Out the Client, the Native VLAN and the SwitchA test matrix that eliminated three SSH clients, keepalives, native-VLAN leakage, a bastion VLAN and two switch vendors, and pointed at the one path that never dropped.#CyberDenResolved (in Part 3) · Series 2 of 32026-01-12Running Security Onion in a Small LabSizing a full NSM stack on a 32 GB mini PC, the installer gotchas, and why placing it in the right segment fixed reachability.#CyberDenRunning2026-01-06ARP Flux on a Dual-NIC VyOS VM: Diagnosis and FixThe core router was healthy but unreachable on management. The cause was a second virtual NIC on another bridge; one NIC, one bridge fixed it.#CyberDenResolved2025-12-12Management-Plane Migrations: Why Mine Failed and the Change Rules I Use NowA VLAN migration that cut every console at once, why a factory reset was the right recovery, and the five change rules that came out of the rebuild.#CyberDenResolved by rebuild2025-11-30The 60-Second SSH Drop, Part 1: An Unmanaged Switch Bridging Two NetworksDead VLANs and sub-minute SSH sessions traced with one tcpdump to a home network leaking into the lab, fixed by isolating the lab and moving to a managed switch.#CyberDenResolved · Series 1 of 32025-11-28Design: A 30-Segment Enterprise-Style Range on Two Mini PCsGrouping ~30 segments into enterprise trust zones, a readable addressing scheme, and the rules that keep hypervisors out of workload segments.#CyberDenDesign (core segments built)2025-11-20A Reusable 5-Node CCNA Topology in EVE-NGOne small topology covering VLANs, trunks, router-on-a-stick, static routing, NAT and management, the same pattern CyberDen runs for real.#CyberDenshort2025-11-19Recovering EVE-NG: Diagnose the Stack Before Repairing ItFrom 403 to 502 to a missing PHP-FPM socket, and the discovery that EVE-NG runs on Apache, which made a clean reinstall the right fix.#CyberDenResolved (reinstall)