cscg24-for2

commit aa75093e0e43ece27948812c0cecf46894c846a2
Author: Louis Burda <quent.burda@gmail.com>
Date:   Mon,  1 Apr 2024 20:39:11 +0200

Add solution

Diffstat:
A
chall/description
 | 
1
+
A
chall/intro-forensics-2.zip
 | 
0

A
solve/flag
 | 
1
+
A
solve/intro-forensics-2.pcapng
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0

A
solve/solve
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12
++++++++++++

5 files changed, 14 insertions(+), 0 deletions(-)
diff --git a/chall/description b/chall/description
@@ -0,0 +1 @@
+We were able to capture a hidden service. Could you recover the secret order?
diff --git a/chall/intro-forensics-2.zip b/chall/intro-forensics-2.zip
Binary files differ.
diff --git a/solve/flag b/solve/flag
@@ -0,0 +1 @@
+CSCG{kn0cking_on_heavens_d000r}
diff --git a/solve/intro-forensics-2.pcapng b/solve/intro-forensics-2.pcapng
Binary files differ.
diff --git a/solve/solve b/solve/solve
@@ -0,0 +1,12 @@
+#!/usr/bin/env python3
+
+from base64 import b64decode
+import subprocess
+import requests
+import re
+
+packet_filter = "ip.src_host == 192.168.178.21 && ip.dst_host == 45.142.177.160 && tcp.flags.syn == 1"
+cmd = f"tshark -nr intro-forensics-2.pcapng -Y '{packet_filter}' -T fields -e tcp.dstport"
+ports = subprocess.check_output(cmd, shell=True).decode().split("\n")
+ports = b"".join([int.to_bytes(int(p), 2, "big") for p in ports if p.strip() != ""])
+print(ports.decode())