Premium Only Content
![Leaking Secret Data with a Heap Overflow - "Leek" Pwn Challenge [Angstrom CTF 2023]](https://1a-1791.com/video/s8/1/T/3/u/s/T3usj.qR4e-small-Leaking-Secret-Data-with-a-.jpg)
Leaking Secret Data with a Heap Overflow - "Leek" Pwn Challenge [Angstrom CTF 2023]
Video walkthrough for the binary exploitation (pwn) challenge, "Leek" from the Angstrom capture the flag (CTF) competition 2023. The challenge involves performing a heap overflow to overwrite all null bytes between our user input chunk and secret data chunk so that when puts() is called, it prints both chunks (there's no null terminator separating them). After this, we need to repair the header of the chunk we modified so that the program can continue execution. We repeat this process of leaking and submitting the random (secret) bytes 100 times, at which point we receive the flag! Write-ups/tutorials aimed at beginners - Hope you enjoy 🙂 #Angstrom #AngstromCTF #CTF #Pentesting #OffSec #Pwn #BinaryExploitation #Reversing #ReverseEngineering
↢Social Media↣
Twitter: https://twitter.com/_CryptoCat
GitHub: https://github.com/Crypto-Cat/CTF
HackTheBox: https://app.hackthebox.eu/profile/11897
LinkedIn: https://www.linkedin.com/in/cryptocat
Reddit: https://www.reddit.com/user/_CryptoCat23
YouTube: https://www.youtube.com/CryptoCat23
Twitch: https://www.twitch.tv/cryptocat23
↢AngstromCTF↣
https://ctftime.org/event/1859
https://2023.angstromctf.com/challenges
https://discord.gg/Dduuscw
https://twitter.com/angstromctf
↢Resources↣
Ghidra: https://ghidra-sre.org/CheatSheet.html
Volatility: https://github.com/volatilityfoundation/volatility/wiki/Linux
PwnTools: https://github.com/Gallopsled/pwntools-tutorial
CyberChef: https://gchq.github.io/CyberChef
DCode: https://www.dcode.fr/en
HackTricks: https://book.hacktricks.xyz/pentesting-methodology
CTF Tools: https://github.com/apsdehal/awesome-ctf
Forensics: https://cugu.github.io/awesome-forensics
Decompile Code: https://www.decompiler.com
Run Code: https://tio.run
↢Chapters↣
Start: 0:00
Patch lib-c (pwninit): 0:20
Test the program functionality: 1:05
Check the binary protections (checksec): 1:37
Analyse decompiled code (ghidra): 3:53
Recap of analysis: 6:51
PwnTools script: 8:40
Setup breakpoints: 14:38
Debug with GDB (pwndbg): 15:33
Heap recap (chunk structure): 16:20
Reviewing vulnerability / exploit: 18:01
Finish PwnTools script: 20:40
Test against remote server: 24:13
Final recap: 25:07
End: 25:56
-
2:25:31
vivafrei
12 hours agoEp. 281: Charlie Kirk; Routh Trial; Charlotte Train; Bolsanaro Defense; SCOTUS & MORE!
93.3K105 -
2:55:38
Turning Point USA
3 hours agoWASHINGTON D.C. PRAYER VIGIL FOR CHARLIE KIRK
38.6K17 -
35:54
The Mel K Show
3 hours agoMel K & Tim James | Healing is an Inside Job | 9-14-25
18.2K2 -
LIVE
IsaiahLCarter
6 hours ago $0.87 earnedCharlie Kirk, American Martyr (with Mikale Olson) || APOSTATE RADIO 028
421 watching -
16:43
Mrgunsngear
10 hours ago $1.35 earnedKimber 2K11 Pro Review 🇺🇸
7.63K11 -
13:40
Michael Button
1 day ago $0.33 earnedThe Strangest Theory of Human Evolution
5.34K10 -
10:19
Blackstone Griddles
1 day agoMahi-Mahi Fish Tacos on the Blackstone Griddle
4.27K1 -
23:51
Jasmin Laine
1 day ago“Stop Wasting My Time!”—Trump's BRUTAL WARNING To Canada As Poilievre ROASTS CBC LIVE
4.12K22 -
9:54
Millionaire Mentor
1 day agoNBC Host EXPOSES JB Pritzker For Saying This About Trump
1.83K4 -
1:35:39
SB Mowing
2 days agoIt took the WHOLE NEIGHBORHOOD to uncover this yards SHOCKING SECRET
86.8K61