Merge branch 'master' of github.com:failedxyz/easyctf

self-modifier/b0.bin

@@ -1,3 +1,3 @@
 SUU<EFBFBD>‹‰û	
 ]òŒÔ#ÓDœöG•Z<12><1C><>)!!"rÛ5¥ã q£­{,./³Ý:À;o°`99:É3,:ÍRÈDºVšTm¸D\IjÌ”Y¡\ÛVXY¨Tœ
-’nsg@è%Gãi•{±qJ<71>avW,†y-ö–z{|$ŒpÙ@ÖÖvŠ—ƒ¬ɇ<07>qŸM<C5B8>¶`›Ï¥™™ši“<69>š»R®ûbVª·£Œ[¥ñ¨‰ö\¿ ¶—ìëàŒ>€»»¼È¶2NüÃÃÄ.ÁJF„ËË̉ŸB“ÕYÓ+Å‹‰‡ƒQ]‹ÜÞßÕ÷<EFBFBD>ºláÖ(`l¼ííî,jh˳¤™“–‹œÚž’‰›<E280B0> ujf$gct|)d~aok}<1`|a{r7lv:-<nwxNHDJGDHSOCLY_K\;234åv^9šÝ®ýgP5a%,0e/3iIÐÒÕò %q6&97xWXYZ[]_][egekmomkege{}}{egekmomkege[]_][¥§¥«­¯­«¥§¥»½¿½»¥§¥«­¯­«¥§¥ÛÝßÝÛåçåëíïíëåçåûýÿýûåçåëíïíëåçåÛÝßÝÛ¥§¥«­¯­«¥§¥»½¿½»¥§¥«­¯­«¥§¥[]_][egekmomkege{}}{egekmomkege[]_][¥
+’nsg@è%Gãi•{±qJ<71>avW,†y-ö–z{|$ŒpÙ@ÖÖvŠ—ƒ¬ɇ<07>qŸM<C5B8>¶`›Ï¥™™ši“<69>š»R®ûbVª·£Œ[¥ñ¨‰ö\¿ ¶—ìëàŒ>€»»¼È¶2NüÃÃÄ.ÁJF„ËË̉ŸB“ÕYÓ+Å‹‰‡ƒQ]‹ÜÞßÕ÷³"èláÖ(`l¼ííî,jh˳¤™“–‹œÚž’‰›<E280B0> ujf$gct|)d~aok}<1`|a{r7lv:-<nwxNHDJGDHSOCLY_K\;234åv^9šÝ®ýgP5a%,0e/3iIÐÒÕò %q6&97xWXYZ[]_][egekmomkege{}}{egekmomkege[]_][¥§¥«­¯­«¥§¥»½¿½»¥§¥«­¯­«¥§¥ÛÝßÝÛåçåëíïíëåçåûýÿýûåçåëíïíëåçåÛÝßÝÛ¥§¥«­¯­«¥§¥»½¿½»¥§¥«­¯­«¥§¥[]_][egekmomkege{}}{egekmomkege[]_][¥

self-modifier/b4.bin

@@ -1 +1 @@
-¼°wþ;$ân6ßi2*­Élu ež5ry ãi<19>åဠriZ?{ hpŽ0ä0$ùæ˜ flêgkß5.NÓâ)ˆW‹ LL$’ræ¶rü
]<05>	U)xˆŠrLO’üM“\(¬l¯%wØ8trrq"˜j9úM8Þ®89:<3A><=>GGÊGÉiH¬qÿJKL…NOP%Y\â_ÜμZ[\ª¼Öæ„bcd¦®ghi±klmbû<rþX{<7B>}£yz{•}~ý<7F><C3BD>5Á<35>€ÏbBbŒ<62>Ž|<7C>‘’–—˜™š›œ<E280BA>žŸ ›µ£¤¥¦§¨©ª‚±ãÁßÕ<C39F>²Œ´µ¶å¸¹º»½¼¼¼ÄÄÄÄÌÌÌÌÄÄÄÄÜÜÜÜÄÄÄÄÌÌÌÌÄÄÄÄüüüüÄÄÄÄÌÌÌÌÄÄÄÄÜÜÜÜÄÄÄÄÌÌÌÌÄÄÄļ¼¼¼DDDDLLLLDDDD\\\\DDDDLLLLDDDD||||DDDDLLLLDDDD\\\\DDDDLLLLDDDD¼¼¼¼ÄÄÄÄÌÌÌÌÄÄÄÄÜÜÜÜÄÄÄÄÌÌÌÌÄÄÄÄüüüüÄÄÄÄÌÌÌÌÄÄÄÄÜÜÜÜÄÄÄÄÌÌÌÌÄÄÄļ¼¼¼DDDDLLLLDDDD\\\\DDDDLLLLDDDD||||DDDDLLLLDDDD\\\\
+¼°wþ;$ân6ßi2*­Élu ež5ry ãi<19>åဠriZ&s hpŽ0ä0$ùæ˜ flêgkß5.NÓâ)ˆW‹ LL$’ræ¶rü
]<05>	U)xˆŠrLO’üM“\(¬l¯%wØ8trrq"˜j9úM8Þ®89:<3A><=>GGÊGÉiH¬qÿJKL…NOP+Y\â_ÜμZ[\ª¼Öæ„bcd¦®ghi±klmbû<rþX{<7B>}£yz{•}~ý<7F><C3BD>5Á<35>€ÏbBbŒ<62>Ž|<7C>‘’–—˜™š›œ<E280BA>žŸ ›µ£¤¥¦§¨©ª‚±ãÁßÕ<C39F>²Œ´µ¶å¸¹º»½¼¼¼ÄÄÄÄÌÌÌÌÄÄÄÄÜÜÜÜÄÄÄÄÌÌÌÌÄÄÄÄüüüüÄÄÄÄÌÌÌÌÄÄÄÄÜÜÜÜÄÄÄÄÌÌÌÌÄÄÄļ¼¼¼DDDDLLLLDDDD\\\\DDDDLLLLDDDD||||DDDDLLLLDDDD\\\\DDDDLLLLDDDD¼¼¼¼ÄÄÄÄÌÌÌÌÄÄÄÄÜÜÜÜÄÄÄÄÌÌÌÌÄÄÄÄüüüüÄÄÄÄÌÌÌÌÄÄÄÄÜÜÜÜÄÄÄÄÌÌÌÌÄÄÄļ¼¼¼DDDDLLLLDDDD\\\\DDDDLLLLDDDD||||DDDDLLLLDDDD\\\\

self-modifier/first.asm

@@ -117,10 +117,10 @@ past_trash:
 	pop edx
 
 	mov eax, dword [esi+temp_val]
-	; 0x61375a7b = little endian of '{Z7a'
-	; 0x61375a7b ^ 0x3fab396d which is the value of the correct input 1.33769
+	; 0x336a687b = little endian of '{hj3'
+	; 0x336a687b ^ 0x3fab396d which is the value of the correct input 1.33769
 	; is equal to 0x5e9c6316
-	xor eax, 0x5e9c6316
+	xor eax, 0xcc15116
 	mov dword [edi], eax
 	xor eax, eax
 	mov dword [esi+temp_val], eax

self-modifier/fourth.asm

@@ -22,14 +22,14 @@ include 'std.inc'
 ; 3 - 5,7 - '_'
 ; 5 - 7,11 - 'e'
 ; 7 - 11,13 - 'x'
-; 11 - 13,17 - 't'
+; 11 - 13,17 - 'z'
 ; 13 - 17,19 - '}'
 ; 17 - 19,23 - '}'
 ; 19 - 23,29 - '}'
 
-; 3 * 7 * 11 * 17 = 3927
-; answer "2 4 6 12"
-; flag _xt}
+; 2 * 7 * 11 * 17 = 0x74e
+; answer "0 4 8 13"
+; flag -ez}
 
 start:
 	push edi
@@ -50,7 +50,7 @@ start:
 	jnz .lp
 
 	mov eax, dword [esi+super_val]
-	cmp eax, 3927
+	cmp eax, 0x74e
 	jnz .bad
 	jmp .finish
 
@@ -116,7 +116,7 @@ above_handler:
 
 eleven:
 	dd thirteen,seventeen
-	db 't',11
+	db 'z',11
 
 mul_handler:
 	movzx eax, byte [ebp+9]

self-modifier/grader.py

@@ -1,13 +1,13 @@
 def grade(random, key):
-    if key.find("Z7a_ok_qfme_xt") != -1:
+    if key.find("hj3-0p9cgfb-ez") != -1:
         return True, "Correct!"
     incorrect_txt = 'Wrong. '
-    if key.find("Z7a") == -1:
+    if key.find("hj3") == -1:
     	incorrect_txt += "Phase 1 failed. "
-    if key.find("_ok_") == -1:
+    if key.find("-0p9") == -1:
     	incorrect_txt += "Phase 2 failed. "
-    if key.find("qfme") == -1:
+    if key.find("cgfb") == -1:
     	incorrect_txt += "Phase 3 failed. "
-    if key.find("_xt") == -1:
+    if key.find("-ez") == -1:
     	incorrect_txt += "Phase 4 failed. "
     return False, incorrect_txt

self-modifier/second.asm

@@ -62,10 +62,10 @@ printLoop:
 
 	mov ecx, dword [esi+inputVal]
 	pop edi
-	; 433695873 is the answer
-	; (struct.unpack('<I', b'_ok_')[0] ^ 0x19d9ac81)
-	; This part of the flag is _ok_ ^ the 35th value in the pattern.
-	xor ecx, 0x46b2c3de
+	; 797691075 is the answer
+	; (struct.unpack('<I', b'-0p9')[0] ^ 0x2f8bccc3)
+	; This part of the flag is -0p9 ^ the 36th value in the pattern.
+	xor ecx, 0x16fbfcee
 	mov dword [edi], ecx
 
 	push edi
@@ -80,7 +80,7 @@ printLoop:
 
 	ret
 
-pattern_text db 'What is the 35th number (index 34) in the following sequence?', 0
+pattern_text db 'What is the 36th number (index 35) in the following sequence?', 0
 format_text db '%d ', 0
 
 ; ecx = arg

self-modifier/third.asm

@@ -92,7 +92,7 @@ fail:
 	mov eax, 0
 	ret
 
-to_match db 'ezpr', 0
+to_match db 'xtnq', 0
 
 idiot:
 	lea ecx, [esi+idiot_text]
@@ -104,7 +104,7 @@ idiot:
 	dec esp
 	ret
 
-alphabet db '{m}krzyjfwngpshteoialduqxvcb|', 0
+alphabet db 'hqxfbntvirwml{cap|z}sjeodygku', 0
 ;            abcdefghijklmnopqrstuvwxyz{|}
-; flag is "qfme"
+; flag is "cgfb"
 resv_stuff 512-$