2021from public repositories
Gctf Beginners 2021
19 challenges with 19 published solutions between them. CTFtime has no listing for this event at all, so nothing built on CTFtime can show what it was made of. These writeups were found in public repositories instead. Each link is pinned to the commit it was read from.
Where these writeups liveUncategorised17
The upstream scoreboard did not say, so neither do we.
1 Novosibirsk Chemical Plant
1 official solution11 Heathrow Secret Warehouse
1 official solution12 Singapore Harbour
1 official solution13 Unknown Aboard Boat
1 official solution14 Unknown Prison Cell
1 official solution15 Unknown Outside Secret Base
1 official solution16 Unknown Prison Cell 2
1 official solution17 Unknown Inside Secret Base
1 official solution18 Unknown Master Office
1 official solution2 Moscow Apartment
1 official solution3 Moscow Streets
1 official solution4 Secret Location Base
1 official solution5 Istanbul Bazaar
1 official solution6 Shenzhen Office
1 official solution7 Buenos Aires Conference
1 official solution8 Croatia Yacht
1 official solution9 Johannesburg Hideout
1 official solution
Cryptography2
Recover a plaintext or a key from something that was supposed to protect it. In practice: identify the scheme, find the parameter the author got wrong, exploit it.
Solve it with:Cipher identifier and automatic decoderVigenere cipher solver with automatic key recoveryRSA decryption and attack runnerWiener’s attack on small RSA private exponentsIn-browser hash cracker with rule transformsLearn: Classical ciphers and frequency analysisLearn: RSA and the parameters that break it
1 simple RSA
1 official solution2 Logical SEESAW
1 official solution