ALL the CTFS of Crypto2025 finally

crypto-simmetric/fool-the-oracle-v2/attack.py

@@ -0,0 +1,108 @@
+#!/usr/bin/env python3
+from pwn import *
+
+HOST = "130.192.5.212"
+PORT = "6542"
+
+server = remote(HOST,PORT)
+sleepT = 0.1
+
+payload = b'A'*32
+flag = "CRYPTO25{ad3c6c1e-5cac-4c87-b5c3-a5dab511fee3}"
+firstBlock = b"CRYPTO25{ad3c6c1"
+secondBlock = b"e-5cac-4c87-b5c3"
+thirdBlock=b"-a5dab511fee3}"
+flagGuessed = b''
+"""for i in range(16):
+    # Create one pad block with the 5 random bytes
+    beforePad = b'A'*11
+    pad = b'A'*(16-(i+1))
+    fPayload = pad + flagGuessed
+    for guess in string.printable:
+        guess = bytes(guess,'utf-8')
+        server.send(b'enc\n')
+        sleep(sleepT)
+        server.recv(1024)
+        sleep(sleepT)
+        print(f"Payload len: {len(fPayload+guess)} Pad len: {len(pad)}")
+        toSend = beforePad+fPayload+guess+pad
+        print(f"Sending {toSend} with len {len(toSend)}")
+        server.send( toSend.hex())
+        server.send(b'\n')
+        sleep(sleepT)
+        #print(server.recv(1024))
+        ciphertext = server.recv(1024)
+        #print(f"Ciphertext:{ciphertext}")
+        ciphertext = bytes.fromhex(ciphertext.strip(b" >").split(b"\n")[0].decode('utf-8'))
+        if ciphertext[16:32] == ciphertext[32:48]:
+            print(f"Block1:{ciphertext[16:32]} Block2:{ciphertext[32:48]}")
+            print(f"Matched guess: {guess}")
+            flagGuessed += guess
+            print(f"Already Guessed: {flagGuessed}")
+            break
+        sleep(sleepT)
+            #ciphertext//AES.blocksize
+"""
+
+"""for i in range(16):
+    beforePad = b'A'*11
+    pad = firstBlock[(i+1):]
+    #pad =  b'A'*(16 - (len(flagGuessed)+1) )
+    fPayload =  pad + flagGuessed
+    #fPayload = b"A"*(16 - (len(fBlock+flagGuessed)+1) )+fBlock+flagGuessed
+    #fPayload = fBlock[(i+1):]+flagGuessed
+    for guess in string.printable:
+        guess = bytes(guess,'utf-8')
+        server.send(b'enc\n')
+        server.recv(1024)
+        sleep(sleepT)
+        #The second pad can be whatever
+        toSend = beforePad + fPayload+guess+pad
+        print(f"Payload len: {len(fPayload+guess)} Pad len: {len(pad)}")
+        print(f"Sending {toSend} with len {len(toSend)}")
+        server.send( toSend.hex())
+        server.send(b'\n')
+        sleep(sleepT)
+        #print(server.recv(1024))
+        ciphertext = server.recv(1024)
+        #print(f"Ciphertext:{ciphertext}")
+        ciphertext = bytes.fromhex(ciphertext.strip(b" >").split(b"\n")[0].decode('utf-8'))
+        if ciphertext[16:32] == ciphertext[48:64]:
+            print(f"Block1:{ciphertext[0:16]} Block2:{ciphertext[16:32]}")
+            print(f"Matched guess: {guess}")
+            flagGuessed += guess
+            print(f"Already Guessed: {flagGuessed}")
+            break
+        sleep(sleepT)
+            #ciphertext//AES.blocksize
+"""
+for i in range(16):
+    beforePad = b'A'*11
+    pad = secondBlock[(i+1):]
+    #pad =  b'A'*(16 - (len(flagGuessed)+1) )
+    fPayload =  pad + flagGuessed
+    #fPayload = b"A"*(16 - (len(fBlock+flagGuessed)+1) )+fBlock+flagGuessed
+    #fPayload = fBlock[(i+1):]+flagGuessed
+    for guess in string.printable:
+        guess = bytes(guess,'utf-8')
+        server.send(b'enc\n')
+        server.recv(1024)
+        sleep(sleepT)
+        #The second pad can be whatever
+        toSend = beforePad + fPayload+guess+pad
+        print(f"Payload len: {len(fPayload+guess)} Pad len: {len(pad)}")
+        print(f"Sending {toSend} with len {len(toSend)}")
+        server.send( toSend.hex())
+        server.send(b'\n')
+        sleep(sleepT)
+        #print(server.recv(1024))
+        ciphertext = server.recv(1024)
+        #print(f"Ciphertext:{ciphertext}")
+        ciphertext = bytes.fromhex(ciphertext.strip(b" >").split(b"\n")[0].decode('utf-8'))
+        if ciphertext[16:32] == ciphertext[64:80]:
+            print(f"Block1:{ciphertext[0:16]} Block2:{ciphertext[16:32]}")
+            print(f"Matched guess: {guess}")
+            flagGuessed += guess
+            print(f"Already Guessed: {flagGuessed}")
+            break
+        sleep(sleepT)