Soreat_u’s Blog

Case Study: Pseudorandom Number Generator

2019-09-22 2024-01-29 Cryptography

A brief study of two PRNGs: LCG and MT19937

Writeup for Many Problems in CNSS Recruit 2019

2019-09-01 2024-01-29 Writeup

Writeup for pwn, web, crypto, misc problems in CNSS Recruit 2019

Writeup for Share in CNSS Summer Camp 2019

2019-08-25 2024-01-29 Writeup

CNSS暑假招新赛的一道Crypto题目的writeup

Writeup for Crypto Problems in SUCTF 2019

2019-08-20 2024-01-29 Writeup

Writeup for 4 crypto challenges in SUCTF 2019 (2019-08-17 09:00 +36h).
- (easy) DSA: exploit the reused ephemeral key k to break DSA
- (easy) Prime: factor n into 4 primes
- (easy) MT: reverse a modified MT algorithm
- (easy) RSA: crack a RSA parity oracle

Summary for Freshman Year

2019-08-19 2024-01-29 Just a Transient Thought

A plain record of the freshman year, and some plans.

Notes on “A Friendly Introduction to Number Theory”

2019-08-16 2024-01-29 Notes

"A Friendly Introduction to Number Theory" 读书笔记

Writeup for Crypto Problems in De1CTF 2019

2019-08-06 2024-01-29 Writeup

Writeup for 3 crypto challenges in De1CTF 2019 (2019-08-03 09:00 +48h).
- (easy) xorz: recover key from stream cipher
- (medium) Babylfsr: reverse a lfsr given (nearly) 2n outputs
- (medium) Baby RSA: crack a nesting RSA

Writeup for Crypto Problems in CyBRICS CTF 2019

2019-07-22 2024-01-29 Writeup

Writeup for 2 crypto challenges in CyBRICS CTF 2019 (2019-07-20 18:00 +24h).
- (easy) Zakukozh: decipher an img file encrypted by Affine Cipher
- (medium) Fast Crypto: optimize a brute-force algorithm using mathematical theories

Writeup for Crypto Problems in SCTF 2019

2019-06-24 2024-01-29 Writeup

Writeup for 2 crypto challenges in SCTF 2019 (2019-06-22 09:00 +36h).
- (medium) warmup: forge AES message to get verified
- (medium) babygame: RSA Broadcast Attack with Linear Padding & forge

Writeup for EasyRSA in 2019神盾杯

2019-06-15 2024-01-29 Writeup

Writeup for Babyrsa in 2019神盾杯 (2019-06-14 09:00 +24h).
- (medium) easyRSA: tackle RSA using 3 attacks