hxp 36C3 CTF

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md15

by kirschju
rev

Difficulty estimate: medium - medium

Points: round(1000 · min(1, 10 / (9 + [2 solves]))) = 909 points

Description:


* Hint: Remember, md15 is a reversing challenge. hxp recommends you stop reading crypto papers. *

After all this recent 0daying within the CTF community we figured eclipsing a standard deprecated hash function might be appropriate. To comply with good scientific practice, the respective research paper is currently being peer-reviewed, and therefore secret. However, according to the PC, hyping the topic and publishing the abstract is okay-ish, so here you go:

MD5 Preimage Attack

Clearly, 3 x MD5 == MD15, right?

Download:

md15-16aad16e8564b324.tar.xz (9.9 KiB)

Solution:

CTFtime Logo CTFtime: Task & Writeups

Solved by:

# Team Time
🥇 pasten 2019-12-29 17:56:50 +0000 UTC
🥈 KJC+f0f+Spotless+SF+mhackeroni 2019-12-29 18:38:10 +0000 UTC