The Neg9 Leaderboard is a very popular directory of hacking, reverse-engineering, cryptography, engineering, and numerous other challenges that lets users track their progress and have some friendly competition among peers to motivate each other and keep their skills sharp.

Stay tuned for a new and improved version of the infamous Neg9 Leaderboard!

List of Challenge Sites

Until then, here is the set of sites that the Neg9 Leaderboard included. Some have unfortunately gone down since the leaderboard began, and that has been noted where appropriate. Please note that while we link to the down sites, the domains or sites may be taken over by untrusted third parties at this time - use caution and good judgement.

Challenge SiteUp/DownDate Checked
Bright ShadowsDown2020-10-28
Embedded Security CTFUp2020-10-28
Exploit Education (formerly: Exploit Exercises)Up2020-10-28
MysteryTwister C3 - The Crypto Challenge ContestUp2020-10-28
Regex CrosswordUp2020-10-28
Reverse Engineering challenges (
Smash The StackUp2020-10-28
The Cipher Challenge - The CiphertextsUp2020-10-28
the cryptopals crypto challengesUp2020-10-28
Under the CTFUp2020-10-28