Offical URL: https://cr.yp.toc.tf/

Crypto CTF is a specialized, annual competition organized by the ASIS Team from Iran, explicitly designed to address the community's demand for high-quality, pure cryptography challenges. Established in 2019 as a response to the often lackluster or guessing-oriented crypto tasks found in general competitions, it focuses exclusively on mathematical rigor and modern cryptographic primitives. The event targets intermediate to elite cryptography enthusiasts, earning a reputation for its grueling difficulty and educational value, often requiring deep knowledge of number theory, algebraic structures, and novel attack vectors rather than simple implementation flaws. Like its general-purpose siblings, it is held online in a Jeopardy format, serving as a dedicated playground for the world's best crypto-breakers to test their skills against research-grade problems.

Long Live Crypto :)

Discord: https://discord.gg/RsvAJtF5Q5

Twitter: https://twitter.com/Crypto_CTF

CTF events

NameWeight
Crypto CTF 202588.25
Crypto CTF 202465.62
Crypto CTF 202359.60
Crypto CTF 202248.20
Crypto CTF 202136.00
Crypto CTF 202024.05
Crypto CTF 201924.05
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