[CTF] Google CTF 2025 - webz : Exploiting zlib's Huffman Code Table
2025. 8. 26. 14:20ㆍCTF write up
1. Overview
2. Background
2-1. google-zlib-Increase-Huffman-Table-Size.patch
2-2. Deflate Algorithm
2-2-1. LZ77
2-2-2. Huffman Coding
3. Code Analysis
3-1. Inflate
3-2. Huffman Table
3-3. Decode
4. Vulnerability
4-1. Unintialized Huffman Code Table
4-2. Exploiting inflate_fast
4-2-1. Integer Overflow (Unexploitable)
4-2-2. PoC
4-2-3. Stream Overflow (Exploitable)
4-2-4. PoC
5. Exploit
- English
https://velog.io/@0range1337/CTF-Google-CTF-2025-webz-Exploiting-zlibs-Huffman-Code-Table-English
[CTF] Google CTF 2025 - webz : Exploiting zlib's Huffman Code Table [English]
webz is a zlib exploitation challenge from Google CTF 2025. The Google-zlib implementation provided in the challenge is not upstream; it’s a version w
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- 한국어
https://velog.io/@0range1337/CTF-Google-CTF-2025-webz-Exploiting-zlibs-Huffman-Code-Table
[CTF] Google CTF 2025 - webz : Exploiting zlib's Huffman Code Table [한국어]
1. Overview webz는 Google CTF 2025에서 출제된 zlib 익스플로잇 문제입니다. 문제에서 주어지는 Google-zlib 구현은 원본이 아니고 임의의 패치가 적용된 버전입니다. 일반적인 오픈소스 익스플로잇 챌린지
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