
FortID CTF 2026 – String Peek and Poke Challenge Writeup
String Peek and Poke is a Linux x86-64 pwn challenge built around a small C++ note program. A user can store a word in one of eight std::string slots, retrieve a slot, or exit. Both note commands accept a signed index without checking whether it lies between 0 and 7. That single mistake lets an…

FortID CTF 2026 – Ultimative PHP Challenge Writeup
Ultimative PHP is a web challenge built around a single PHP 8.3 migration endpoint. A request must claim administrator access, provide two distinct recovery answers with equal fingerprints, satisfy an unusual comparison between MD5 and SHA-256 prefixes, and submit a Base64url-encoded PHP profile. The checks appear independent, but they process the same attacker-controlled query string…

SunshineCTF 2026 – Mad Libs Challenge Writeup
Mad Libs is a 64-bit Linux binary exploitation challenge built around a small program that asks for eight words and prints each answer back. The program passes every answer directly to printf as its format string. That mistake gives an attacker both an information disclosure primitive and a memory write primitive. The supplied executable is…

Hack The Box – pcalc Challenge Writeup
pcalc is a small PHP calculator packaged with its application source, web-server configuration, and Docker startup script provided. A visitor supplies an arithmetic expression through the formula query parameter and sees the calculated value in the page. Source inspection shows that the startup script moves the flag out of the web root and gives it…

SunshineCTF 2026 – Homemaker Challenge Writeup
Homemaker is a Linux binary exploitation challenge built around a small, custom command protocol. The supplied program presents itself as a domestic automaton and waits for a service key card, but the useful behavior is in its binary packet parser. A valid key unlocks commands that update and read back a stack-resident state buffer. The…

WebVerse Pro – Proxy Pursuit Challenge Writeup
Proxy Pursuit is a black-box web challenge set in LoadMesh’s operations console. The console displays connection records for a client IP, but it takes that IP from the HTTP X-Forwarded-For header, which a requester can influence. The challenge begins with supplied console credentials and an exposed web endpoint; the goal is to find how this…

Hack The Box – Intergalatic Bounty Challenge Writeup
Intergalatic Bounty is a source-assisted web security challenge built from two Express applications: a bounty-management service and a small webmail viewer. The principal application uses SQLite through Sequelize, JSON Web Tokens for authentication, Nunjucks for server-side templates, sanitize-html for user-supplied bounty descriptions, Nodemailer for account-verification messages, Needle for server-side HTTP requests, and @christopy/mergedeep when administrators…

