stack-the-flag-2020

Can COViD break Alice’s design?

This is the second challenge from the Cryptography section of Stack-The-Flag 2020 by govtech-csg. It uses LFSR stream cipher to encrypt 500 bytes of data and...

Can COViD steal Bob’s idea?

This is the first challenge from the Cryptography section of Stack-The-Flag 2020 by govtech-csg. The challenge wants us to break vulnerable Diffie-hellman pa...

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bamboofox-ctf-2021

Gamer’s Cipher

This is the first challenge from the Cryptography section of BambooFox CTF 2021. It introduced Nimber field and do encryption using it.

ORZ network

This is the third challenge from the Cryptography section of BambooFox CTF 2021. The challenge wants us determine if a Diffie-hellman parameter is vulnerable...

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dso-nus-ctf-2021

YALA (PART 1)

This is the fourth challenge from the Mobile section of DSO-NUS CTF 2021. The challenge needs us to brute force the password for the user.

Sekret

This is the second challenge from the Mobile section of DSO-NUS CTF 2021. The challenge needs us to find the password of a user using OSINT.

Sighhh

This is the third challenge from the Web & Crypto section of DSO-NUS CTF 2021. The challenge uses digital certificate extension with ASN.1 encoding to st...

Protect the Vaccine

This is the second challenge from the Web & Crypto section of DSO-NUS CTF 2021. The challenge introduced a new LSB attack on Special-Structured RSA Prime...

Poor Men

This is the first challenge from the Web & Crypto section of DSO-NUS CTF 2021. The challenge introduced a different variation of RSA that is safe from ac...

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ctf-sg-2021

Live From Serangoon Road

This is the third challenge from the Crypto section of CTF SG 2021. The challenge needs us to break a Stream Cipher that uses 4 LFSR.

GRIC

This is the second challenge from the Crypto section of CTF SG 2021. The challenge needs us to find out the checksum letter when given a 10 digit number.

Long Long Encrypt

This is the first challenge from the Crypto section of CTF SG 2021. The challenge introduced a different variation of RSA that uses \(n = p^{q}\)

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standcon-2021

Space Noise

This is a challenge from Cryptography section of Standcon 2021. The challenge wants us to guess the encryption scheme

Ingenuity Installer

This is a challenge from Cryptography section of Standcon 2021. The challenge wants us to forge a signature of a zip file.

Interstellar Chat

This is a challenge from Cryptography section of Standcon 2021. The challenge uses AES_CTR to encrypt stuff

Mind Reader

This is a challenge from Cryptography section of Standcon 2021. The challenge wants us to break the PRNG system.

Rocket Ship Academy

This is a challenge from Cryptography section of Standcon 2021. The challenge provide you an encrypted text and a decryption oracle.

Substitution Extreme

This is a challenge from Cryptography section of Standcon 2021. The challenge used subsitution cipher to encrypt a text.

Space Papaya

This is a challenge from Cryptography section of Standcon 2021. The challenge used bad parameters for RSA encryption

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acsc-2021

Swap on Curve

This is the fourth crypto challenge from ASCS 2021. It is an interesting question related to ECC.

CBCBC

This is the second crypto challenge from ASCS 2021. It tried to use double AES CBC to protect against padding oracle attack.

RSA stream

This is the first crypto challenge from ASCS 2021. It used Stream cipher with RSA to encrypt a message.

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wargames-2022

Wargames My 2022

Writeup for the challenges I solved in Wargames My 2022

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acsc-2023

ACSC 2023

Writeup for the challenges I solved in ACSC. I mainly focused on Crypto challenges.

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aboh-2023

ABOH 2023

Writeup for all the crypto challenges I solved in Apu Battle of Hackers 2023 (ASEAN Category).

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wargames-2023

Wargames My 2023

Writeup for the challenges I solved in Wargames My 2023

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