https://blog.riverxia.sh/bloghttps://blog.riverxia.sh/post16.htmlpostfix, dovecot, rspamd, opendkim and roundcube on a cheap vps so i can have a real address on my own domain. the dns you actually need, and every dumb thing that broke on the way.https://blog.riverxia.sh/post15.htmlWhy I wrote my own CTF platform from zero in Rust. Hand-rolled SMTP and JWT, sandboxed rhai scripting in every corner, per-team Kubernetes instancing, SSE notifications, and a fully headless API. A build log.https://blog.riverxia.sh/post13.htmlA Schnorr proof whose response is reduced mod the wrong prime. Two stages, two RNGs — a truncated LCG cracked with a lattice, and MT19937 rebuilt from GF(2) relations on the leaked responses.https://blog.riverxia.sh/post14.htmlAn enterprise WiFi RADIUS server that trusts a public CA for client auth. Grab a free Actalis S/MIME cert, present it as your EAP-TLS client cert, and you're staff.https://blog.riverxia.sh/post12.htmlA multivariate-quadratic signature with no norm check. The 200 published signatures leak the hidden basis — BKZ it back, read off the secret p·I/q·I blocks, and forge with four squares.https://blog.riverxia.sh/post11.htmlsmartfella ctf fr. the best osint chain i've ever seen, a 20-hop rabbit hole.https://blog.riverxia.sh/post10.html16 solves, 6 writeups. we went hard on this one. italian CTF with rome finals for top 5.https://blog.riverxia.sh/post9.htmlFull static analysis of a JNI-obfuscated Minecraft cheat client with a bundled RAT — custom Zig AOT compiler, IEEE 754 string encryption, and goto-spaghetti bytecode decryption.https://blog.riverxia.sh/post6.htmlKnown-plaintext XOR crib attack on a fake PDF to recover a 16-byte repeating key.https://blog.riverxia.sh/post7.htmlDouble extension upload bypass on nginx + PHP-FPM to get arbitrary file read.https://blog.riverxia.sh/post8.htmlCustom CTFd deployment with Cloudflare Tunnel, per-player instancing, WebSocket bridge for nc challenges, and a theme that actually looks good.https://blog.riverxia.sh/post5.htmlCSS attribute selectors meet Redis LRU eviction in a 500-point side-channel challenge.https://blog.riverxia.sh/post4.htmlits a shitpost dont expect effort herehttps://blog.riverxia.sh/post3.htmlLambdas lambda'ing all over control codes. Don't you love it?https://blog.riverxia.sh/post2.htmlIt's not because it's such a perfect language...https://blog.riverxia.sh/post1.htmlHow I built a (somewhat) secure markdown-based blog engine that compiles at runtime using vanilla JS and Firebase, completely skipping modern build steps or server infrastructure.