nullcon HackIM 2016 -- Crypto Question 3

Posted 2020-06-13

After entring the luxurious condomium,you get the feel that you are in home of a yester Star. the extravagant flooring and furnishings shows the richness of this star. But where is she? There she is, lying peacefuly on her couch. See what Envy has done to her...with a perfectly well maintained attractive body she still looks sex diva, except for her face beyond recogniton. Her identity is crucial to know who killed her and why? In absence of any personal data around there is only a file. with a cryptic text in it. Preity sure she has used her own name to XOR encrypt the file. And challenge is to know her name.

AncientSecretsOfTheKamaSutra.txt

 

就是找xor的密码，是电影Ancient Secrets Of The KamaSutra的一个人的名字。

把文件 AncientSecretsOfTheKamaSutra.txt 上传到 XOR Cracker（https://wiremask.eu/tools/xor-cracker/），得到了数据：

The most probable key lengths

Possible keys

Key Length	Probability	Guess Keys
2	11.6%
4	13.6%
6	13.1%
8	10.6%
12	15.6%
15	7.0%
18	7.9%
20	6.5%
24	8.4%
36	5.7%
Keys		Decrypted File
J $+na ine	4a 20 24 2b 6e 61 20 03 69 6e 65 0a
J $+na ineK	4a 20 24 2b 6e 61 20 03 69 6e 65 4b

长度最有可能是12， key 可能是：J $+na ine， 然后google "Ancient Secrets of the Kama Sutra", 在 IMDB上看到了一个名字：Jeanna Fine， flag:

Jeanna Fine