https://blog.stellarvector.be/Recent content on Stellar Vector BlogHugoen-usFri, 01 Mar 2024 00:00:00 +0000https://blog.stellarvector.be/writeups/2023/ctf101/sightseeing-in-ghent/Fri, 01 Mar 2024 00:00:00 +0000https://blog.stellarvector.be/writeups/2023/ctf101/sightseeing-in-ghent/OSINT adventure in Ghent requiring landmark identification, Google Maps investigation, and decoding a hidden sequence from a YouTube video soundtrack.https://blog.stellarvector.be/writeups/2023/hackthebox-university-ctf-brains-bytes/gatecrash/Mon, 11 Dec 2023 00:00:00 +0000https://blog.stellarvector.be/writeups/2023/hackthebox-university-ctf-brains-bytes/gatecrash/Deep dive into Nim-specific CRLF injection (CVE-2020-15693). Shows how to inject JSON payloads into headers to bypass frontend filters and achieve SQL injection.https://blog.stellarvector.be/writeups/2023/hackthebox-university-ctf-brains-bytes/mayday-mayday/Mon, 11 Dec 2023 00:00:00 +0000https://blog.stellarvector.be/writeups/2023/hackthebox-university-ctf-brains-bytes/mayday-mayday/Advanced RSA attack exploiting MSB leaks from CRT exponents. Uses the Coppersmith method and lattice-based reduction to factor large moduli.https://blog.stellarvector.be/writeups/2023/hackthebox-university-ctf-brains-bytes/phantomfeed/Sun, 10 Dec 2023 00:00:00 +0000https://blog.stellarvector.be/writeups/2023/hackthebox-university-ctf-brains-bytes/phantomfeed/Multi-stage web exploitation involving a ReDoS-powered race condition, OAuth2-based XSS for token theft, and a final RCE via HTML2PDF font abuse.https://blog.stellarvector.be/writeups/2023/lakectf/keysharer/Mon, 06 Nov 2023 00:00:00 +0000https://blog.stellarvector.be/writeups/2023/lakectf/keysharer/High-level Cryptography solve demonstrating the Invalid Curve Attack. Explains how to recover a secret key by sending points from curves with lower orders.https://blog.stellarvector.be/writeups/2023/ctf101/encoding-challenges/Fri, 20 Oct 2023 00:00:00 +0000https://blog.stellarvector.be/writeups/2023/ctf101/encoding-challenges/Step-by-step guide to reversing complex data encodings. Covers nested Base64/Base16 loops and a custom bit-shifting ‘magic shuffle’ algorithm.https://blog.stellarvector.be/writeups/2023/ctf101/rsa-challenges/Fri, 20 Oct 2023 00:00:00 +0000https://blog.stellarvector.be/writeups/2023/ctf101/rsa-challenges/Comprehensive walkthrough of three RSA challenges from CTF101, covering basic decryption, factoring using online tools, and exploiting totient multiples from leaked private exponents.https://blog.stellarvector.be/writeups/2023/ctf101/substitution-ciphers/Fri, 20 Oct 2023 00:00:00 +0000https://blog.stellarvector.be/writeups/2023/ctf101/substitution-ciphers/Classic cryptography overview featuring Caesar and Vigenere Ciphers. Demonstrates single-byte XOR bruteforcing and frequency analysis for multi-key XOR decryption.https://blog.stellarvector.be/writeups/2023/ctf101/sightseeing/Sun, 15 Oct 2023 00:00:00 +0000https://blog.stellarvector.be/writeups/2023/ctf101/sightseeing/OSINT challenge solve involving Leuven landmark recognition, Google Maps review scouting, and a creative hex-to-ASCII video transcription puzzle.https://blog.stellarvector.be/writeups/2023/ctf101/poster-thief-1/Wed, 11 Oct 2023 00:00:00 +0000https://blog.stellarvector.be/writeups/2023/ctf101/poster-thief-1/Introduction to the security.txt standard (RFC 9116). Shows how to locate and use a site’s security policy to find hidden contact information and flags.https://blog.stellarvector.be/writeups/2023/ctf101/poster-thief-2/Wed, 11 Oct 2023 00:00:00 +0000https://blog.stellarvector.be/writeups/2023/ctf101/poster-thief-2/Detailed exploration of Path Traversal vulnerabilities. Explains how to bypass non-recursive traversal filters by nesting sequences to reach sensitive system files.https://blog.stellarvector.be/writeups/2023/ctf101/poster-thief-3/Wed, 11 Oct 2023 00:00:00 +0000https://blog.stellarvector.be/writeups/2023/ctf101/poster-thief-3/Hands-on tutorial on manipulating HTTP headers using curl. Demonstrates how to bypass server-side checks for User-Agent, Referer, and custom headers.https://blog.stellarvector.be/writeups/2023/downunderctf/apbq-rsa-1/Thu, 07 Sep 2023 00:00:00 +0000https://blog.stellarvector.be/writeups/2023/downunderctf/apbq-rsa-1/RSA factoring challenge using specific linear combination hints. Employs a brute-force GCD attack on coprime hint coefficients to recover the private key.