## 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...

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...

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...

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

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...

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.

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.

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...

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...

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...

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.

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.

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

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

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

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

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

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

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

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

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

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

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