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🔒 UMDCTF 2023 / 🩸-rev-well-connected
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Sutx BOT 04/28/2023 3:00 PM
Well connected - 500 points
Category: Rev Description: I pulled up to a party but they wouldn't let me in until I named 40 functions! 😡 Author: birch Files:Tags: No tags.
04/28/2023 3:00 PM
Sutx pinned a message to this channel. 04/28/2023 3:00 PM
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Sutx BOT 04/28/2023 3:14 PM
@Legoclones wants to collaborate 🤝
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Legoclones 04/28/2023 3:16 PM
stripped, dynamically linked ELF
15:16
also 10 mb....
15:19
main function just prints and leaves.... so flag must be found in a function that is never called. So we're looking for a needle in a haystack
15:19
Cuz there's 10 MB of unnamed functions lol
15:23
And they all look like this with a different number of functions and different params
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Sutx BOT 04/28/2023 3:34 PM
@Violin wants to collaborate 🤝
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Legoclones 04/28/2023 3:38 PM
Lol you wanna see how many functions are called by each other?
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15:38
Answer - all of them 😭
15:38
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15:41
over 10000 functions 28983 functions (edited)
15:41
computer is now frozen
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Legoclones 04/28/2023 4:04 PM
Here are the C files from this (courtesy of Ghidra)
final_only_calls.c
17.52 MB
final2.c
17.53 MB
16:08
hahaha just as I expected
16:09
there are 28960 functions in final_only_calls.c, and only 28959 are called - we gotta find the last one
16:10
The function that is never called is FUN_006e347b
16:15
oooooh I'm gonna blood
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Legoclones
used /ctf submit
Sutx BOT 04/28/2023 4:20 PM
🩸 Well done, you got first blood!
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