Different Techniques used to deploy SQLi attacks as a way of exploiting the database and the website vulnerabilities

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This research paper analyses the different types of vulnerabilities and SQL attacks which can retrieve and manipulate the information of the records stored in the database. It also covers the countermeasures which should be taken to resolve the issues of SQLI.

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SQL Injection: Database
Security

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Contents
I. Introduction...................................................................................................................................2
Problem Statement.............................................................................................................................3
Research Aim....................................................................................................................................3
Research Objectives..........................................................................................................................3
Research Questions............................................................................................................................4
II. Understanding types of SQL injection...........................................................................................4
Key Concepts....................................................................................................................................4
Classification of SQLI on the basis of Intent:....................................................................................4
Classification of SQL on the basis of type:........................................................................................5
Consequences of the SQL query injection.........................................................................................7
III. Literature Review:.....................................................................................................................7
IV. SQLIA Countermeasures...........................................................................................................9
V. Prevention Procedures from SQL injection..................................................................................11
VI. Evaluation................................................................................................................................11
VII. Proposed Approach..................................................................................................................12
Algorithm for Hash Value...............................................................................................................12
VIII. Conclusion...............................................................................................................................14
IX. References:..............................................................................................................................15
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Title: Different Techniques used to deploy SQLi attacks as a way of exploiting the database
and the website vulnerabilities
I. Introduction
The SQL injection is the programming code which is used for exploiting the database by
making use of web hacking technologies. The SQL statement is get incorporated with the
malicious code which is given as input to exploit the functionality of the database. The
functionality of the database server can be controlled by the SQL injection. The
vulnerabilities and the malicious code which get associated with the SQL query is used for
changing the operational programming of the database to get accurate information. The
attacker can retrieve the text and the information from the database by getting bypassing
through the authentication and authorization technique of the web by making use of SQL
injection technique (Tajpour, Ibrahim, and Masrom, 2011). The integrity of the database can
be gets affected through the SQLI because it is capable of doing modification and deletion of
the tuples from the RDBMS. The confidential information of the personal get hacked through
the unauthenticated accessing of the records which contains information relevant to secrets of
the business, confidential information of the customers, bank details, CVC number,
password, and others. The SQL injection malicious code can be identified during the time of
compilation. It helps in analysing the malicious code at the byte code level of SQL program.
The algorithm based on automation prepared statement is used for removing the malicious
code which is added to the SQL statement. The payload is added in the SQL query for
developing SQLI for the attack on the database. In this paper, we are looking forward to
research on the different types of vulnerabilities and SQL attacks which can retrieve and
manipulate the information of the records stored in the database. We will also undertake the
research study on the countermeasures which should be taken to resolve the issues of SQLI.
The following figure shows the example of the SQL injection on the database. It can be
predicted from the figure below that the malicious code get inserted by the hacker through the
SQL statement for manipulating the information stored in the database.
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(Source: Qian, Zhu, Hu, and Liu, 2015). Research of SQL injection attack and prevention technology. 1st ed.)
Problem Statement
SQLI is the hacking technology which is used for retrieving the information from the
database. The malicious code and vulnerabilities are sent by the attacker in the SQL
statement which exploits and manipulate the information of the database. The accuracy and
integrity of the data stored in the database can be exploited with the SQLI query posted on
the database. The consequences of the SQL injection on the databases are problem of
authorization, authentication, and loss of confidentiality and integrity of the data stored in the
database.
Research Aim
The aim of the research study is to analyse the research on the different types of
vulnerabilities and SQL attacks which can retrieve and manipulate the information of the
records stored in the database. We will also undertake the research study on the
countermeasures which should be taken to resolve the issues of SQLI.
Research Objectives
The objective of the research is to find out:
Type of SQL injection
Prevention techniques from the SQL injection

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Countermeasures and associated results to resolve the SQL injection problem
Evaluation of the countermeasures attack
Research Questions
What is SQL injection?
What are the Different Techniques used to deploy SQLi attacks as a way of exploiting the
database and the website vulnerabilities?
II. Understanding types of SQL injection
Vulnerabilities and malicious codes get associated with the SQL statement to retrieve data
from the database which affects the accuracy of the information stored in the records. This is
due to the SQL injection. It directly affects the confidentiality, accuracy, and integrity of the
data stored on the database.
Key Concepts
SQL injection is the type of malicious code which is attached with the SQL query and sent to
the SQL interpreter for getting the relevant data from the SQL database. The SQL interpreter
does not predict the malicious code of the SQL statement. The SQL command drafted by the
hacker is used for retrieving the information from the database. The vulnerabilities exploits
the orientation and the integrity of the data stored on the database. The confidential data of
the personal is hacked from the account even though it has authorised and authenticated
prevention method.
Classification of SQLI on the basis of Intent:
Process of data extraction:
This type of attack is used for extracting data from the records of the database. The
confidential information of the user such as bank details and password can be hacked.
Manipulation of the data:
The SQL query is designed for changing and manipulating the information of the database
according to the choice hacker without any notification to the user.
Finger printing process on the database:
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The malicious code is added to the SQL query for developing a protocol for getting
authorization and authentication to retrieve the information from the database.
By passing Attack:
The SQL query is designed for bypassing the authorisation and authentication information of
the database. The user directly use the information of the database.
Identification of the Vulnerable parameter:
It is used for accessing the information by SQL query by making a vulnerability scanner
automation tool.
Identification of the database schema:
The SQL query is designed for retrieving the information of the database schema like table
name, data types, and other attributes
Classification of SQL on the basis of type: Tautology:
The Tautology is the attack in which conditional query is generated by the attacker for
accessing the required data. The conditional statement used in the SQL query always
answered true which helps in accessing the data and information (Kindy, and Pathan, 2012).
Example:
SELECT * FROM BANKACCOUNT WHERE Customer=” or 1=1
When the above query is executed by the database server than the result true will be
generated every time. The rejection of the SQL query processed result in the generation of
debugging information which is useful for the hacker to access the required information of
the database (Morgenroth, 2018).
Incorrect Logical Queries:
The rejection of the SQL query due to incorrect logic design processed result in the
generation of debugging information which is useful for the hacker to access the required
information of the database. The vulnerability parameters are used for accessing the
information (Sajjadi, and Pour, 2013).
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Example:
SELECT * FROM BANKACCOUNTS WHERE Customer=” or 1=1 AND pass =” AND
FAIL
The error message is generated by typing SQL query for accessing the database.
Union Query:
The UNION clause is used for adding unauthorized SQL statement with the authorized SQL
statement. On typing the query given below the statement will return no result while on the
execution of the second query all the details from the customer’s account get retrieved.
Example:
SELECT * FROM BANKACCOUNTS WHERE Consumer=” UNION SELECT * FROM
Customer AND FAIL=” AND eid =
The information from the customer Table will be provided to the hacker on the execution of
the statement attached to the UNION SQL operation
Piggy Backed Query:
This query is added to the original statement of SQL query. It make use of “.” Delimeter from
destroying and manipulating the information stored on the database.
SELECT * FROM BANKACCOUNT Where CUSTOMER =”; drop table
BANKACCOUNTS-‘ AND FAIL=” AND eid =’
This query retrieves all the confidential information of the customer related to their bank
account.
Blind Injection Queries:
In this query, the error information is hide related to the retrieval of information from the
database. The error message of the query is hide by the attacker and he provide only the
general page of the SQL query statement.
Example:

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SELECT * FROM BANKACCOUNTS WHERE Customer=’ Customer1’ AND pass =”
AND eid=
The security parameters can be passed by making use of the above query statement.
Alternate encoding query:
This query is used for converting the data into ASCII code and Hexadecimal code.
Example:
SELECT * FROM BANKACCOUNTS WHERE Customer=’ Customer1’; exec
(char(0x87654dd77865u345e) AND pass =” AND eid=
The result of the above query is the generation of character presented in the bracket into the
ASCII code and the hexadecimal.
Consequences of the SQL query injection
The exploitation of the SQL query can result in damaging the accuracy of the database
because the attacker can manipulate the information by applying the operation like adding of
information, deletion of information, deletion of information, reading of information and
others. The database server gives the authorisation and authentication to read the content of
the database due to the SQL injection query to the hacker (VarunKumar, Prabakaran, Kaurav,
Chakkarvarthy, Thiyagarajan, and Venkatesh, 2014). The hacker can retrieve the
authorisation by drafting a SQL query program for manipulating the information stored on
the database with the use of WRITE operation. The hacker can exploit the accuracy and the
integrity of the data stored at the database. The confidentiality of the personal information of
the user will get hacked by the attacker by generating a select query whose result is always
“YES” after accessing it. The database server will provide the relevant information on
demand by the attacker through the SQL injection in the SELECT and the UNION query.
III. Literature Review:
The SQL injection is the most serious problem because it can exploits the orientation and the
integrity of the data stored in the database (Zhu, 2015). There are various techniques are
proposed by the researchers to overcome the problem of SQL injection which can be
categorised as penetration testing, filtering method, analysis of the information flow, and
coding and programming of defensive measures. The technique of static analysis and
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processing of monitoring program is used for analysing the queries of the database (Gosnik,
2015). The analysis of the SQL program can be effectively done with the deployment of
legitimate processing model. The dynamic runtime of the legitimate model helps in
predicting the effective execution of the database. The SQL injection malicious code can be
identified during the time of compilation. It helps in analysing the malicious code at the byte
code level of SQL program. The algorithm based on automation prepared statement is used
for removing the malicious code which is added to the SQL statement. The most acceptable
SQL injection prevention method is the development of the Hash Function algorithm. The
hash value helps in generating the layer of protection to the user ID and password for
authentication. The hash value is used for testing the authentication of the user ID and
password for approving the authorization to the database (Halde, 2008). The development of
the hash value is the most acceptable model of eliminating the malicious code from the SQL
query drafted for accessing the data from the database. The hash value helps in generating the
layer of protection to the user ID ad password for authentication. The hash value is used for
testing the authentication of the user ID and password for approving the authorization to the
database. The web database makes use of fine grained access control to give access control to
the manipulation of the database. The traceability program should be arranged for analysing
the vulnerability and malicious code attached with the SQL command. The stored procedures
are used for developing the subroutines used for making call of the information from the
database (Halfond, Viegas, and Orso, 2015). The algorithm procedures are developed for
removing the SQL injection from the SQL query which are based on Prepared Statement
Replacement procedures. The source code are analysed for removing the association of the
malicious code. The PSR algorithm is used for analysing the attacks through by By-passing
the authorisation and authentication procedures from the Web portal, finger printing attack of
the database, use of UNION query though injection procedure, and many others. The SQL
checker is used for tracing the SQL query for identifying the SQL command drafted for
retrieving data from the database (Johari and Sharma, 2012). The JAVA SERVER PAGEs
are created for analysing the malicious codes attached with the drafted query by making use
of SELECT and UNION function (Namdev, Hasan, and Shrivastav, 2012). The following
figure shows the detection of the SQL injected Query and according accessing to the
database.
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(Source: Qian, Zhu, Hu, and Liu, 2015). Research of SQL injection attack and prevention technology. 1st ed.)
IV. SQLIA Countermeasures
There are various methods proposed for countermeasures for the SQL injection query on the
SQL statement for accessing the information from the database account of the user.
Code Based SQL injection query detection techniques: This technique is used for testing the
vulnerabilities associated with the SQL query drafted for accessing the database information.
The procedures are developed for finding the program code free from vulnerabilities. The
prototyping tool which is generally used for static analysis in the access point of the database
is SQL UNIT GEN protocol (Janot, and Zavarsky, 2015).
Generating procedures for concrete attack process: This technique is used for automatically
analysing the test input which is provided in the SQL Query. The execution of the program
code which are accused of SQL vulnerabilities can be detected through performing numeric
operations. The numerical operations are performed on the string operation to detect the
vulnerabilities associated with the program code.
Prevention procedures based on learning: The monitoring of the SQL server and the database
server helps in analysing the occurrence of the vulnerabilities associated with the SQL
queries. The legitimate procedures are used for sending the SQL queries for accessing the

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data from the database. The syntactic structure is developed of queries for retrieving and
accessing of the information.
Algorithm procedures for Elimination of SQL injection from the SQL query:
The algorithm procedures are developed for removing the SQL injection from the SQL query
which are based on Prepared Statement Replacement procedures. The source code are
analysed for removing the association of the malicious code. The PSR algorithm is used for
analysing the attacks through by By-passing the authorisation and authentication procedures
from the Web portal, finger printing attack of the database, use of UNION query though
injection procedure, and many others. The integrity of the program code is used for
eliminating the SQL injection malicious code from the SQL program.
Checking of the SQL injection malicious code through the process of mutation:
The malicious code associated with the SQL statement can be checked through the process of
mutation. The mutation programs are written on JAVA server pages for checking and
analysis of the SQL query. The fault based testing procedures are used for analysing the
presence of vulnerabilities in the drafted SQL query with the use of SELECT and UNION
query procedures. The mutant programming makes use of mutation operator to check the
source code for anomalies.
Syntatic testing for SQL injection procedures:
This technique is used for debugging of the SQL query during the request and response
sending procedures between database and web application server. The interpretation of the
SQL query helps in analysing that the right information should be provided to the authorised
user. The parse trees values are used for comparing the values of the SQL query drafted for
retrieving the information. The PINPOINT is generated for analysing the request of attack
send by the hacker.
Adaptive intelligent intrusion detection SQL:
Case Based reasoning system is used for artificial neural network and support vector
machine. The clustering mechanisms are used for developing support vector machine for
detecting the presence of anomalies. The clustering mechanisms are used for the
virtualization network to predict the SQL injection in the SQL query.
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Token query based approach:
This procedure is used for preventing the SQL injection attacks in the SQL query drafted for
accessing the confidential information of the customers from the database. Tokens are
generated for analysing the behavioural pattern used for posting the query of the accessing
the required information (DB Networks, 2015).
V. Prevention Procedures from SQL injection
There are different techniques used for preventing the database from the SQL injection attack
proactively before its occurrence. JDBC checker is used for detecting the occurrence of
anomalies in the SQL query. The mismatching in the statement can result in the occurrence of
anomalies procedures. The Tautology checker is placed for resolving the issue associated
with the Tautology security structure in the SQL injected query. The static analysing
framework is developed for identifying the presence of vulnerabilities in the SQL query
(Clarke, 2015). The dynamic algorithms are designed for checking the SQL query during the
runtime procedures.
VI. Evaluation
During the course program, we have analysed various countermeasures and prevention
technique for resolving the problems associated with thee SQL injection program designed by
the hacker for accessing the information from the database. Different mechanisms are applied
for predicting the presence of SQL injection in the query (Rua, Thiyap, Musab and
Abdulqader, 2017). There are various types of SQL injection used for hacking such as
Tautology, incorrect logic of SQL query, piggy backing SQL injection, and others. Each type
of SQL injection can be resolved by more than one countermeasure. The most appropriate
mode for overcoming the SQL injection problem is the HASH model and Algorithm
procedures. The automated programs are generated by implementing the countermeasure
technique. The table below shows the percentage of resolving the complexity of the SQL
injection through the countermeasures techniques:
Type of Attack Capability of the
technique in
preventing the SQL
injection attack
Capability of the
technique used for
addressing the type
of SQL injection
Capability of the
technique in
preventing the SQL
injection attack
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attack
Tautology Attack 62% 43% 4%
Incorrect SQL query 55% 34% 8%
Piggy Back SQL
query
59% 34% 3%
Union Query 59% 34% 5%
Interference 35% 34% 4%
Alternate Encoding
query
49% 34% 13%
VII. Proposed Approach
The most acceptable SQL injection prevention method is the development of the Hash
Function algorithm. The hash value helps in generating the layer of protection to the user ID
and password for authentication. The hash value is used for testing the authentication of the
user ID and password for approving the authorization to the database. The extra column is
required for storing the hash value for preventing the SQL injection. The hash value related to
user login credential i.e. login ID and password get stored in the database (Angel and
Chandrasekhar, 2017).
Algorithm for Hash Value
The authentication protocol is used for developing SQL injection protector for the database.
The first column represent the hash value for the user name or ID and the second column
represent the hash value for password (Singh and Kaur, 2012). The verification and
validation of the user login and password by comparing it with hash value stored in the
column information of the database (Adhyary, 2016). The calculation of the hash value at run
time helps in providing SQL injection protector for the database. The following diagram
shows the System protection mechanism for the detection and prevention of SQL injection.

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(Source: Qian, Zhu, Hu, and Liu, 2015). Research of SQL injection attack and prevention technology. 1st ed.)
. The hash values are compared for giving authentication to access the database. The
modification in the query is easily predicted through the comparison with the hash value
stored in the database. The rejection of the hash value helps in detecting the anomalies
associated with the SQL query used for getting authentication of the user database and
account. The rejection of the hash value helps in protecting the database from the
manipulation of the information stored on it. The hacker cannot be able to bypass the process
of authorization and authentication. The analysis of the User ID and password through the
generated hash value of the login credential and those which are stored in the database helps
in predicting the occurrence on the anomalies. The programming code drafted for the SQL
query to inject the SQL attack by designing the SELECT query for the attack can be
predicted by the hash value during the dynamic run time of the query. The following diagram
shows the schematic procedures used for detecting and preventing the database by making
use of hash value.
Document Page
(Source: Qian, Zhu, Hu, and Liu, 2015). Research of SQL injection attack and prevention technology. 1st ed.)
The procedure of developing the hash value for the login credential of the user at the backend
query with the use of SQL statement and UNION statement helps in analyzing the anomalies
of the SQL query. The unique hash value is generated for the particular information of the
user ID and Password which get stored in the database at the backend. The SQL injection is
done through the SQL query by adding malicious statement in the SELECT query to get the
output “YES” whenever processed. The authentication to the user will be provided by
comparing the HASH value and matching it for generating the message of NOT SQL
INJECTION.
VIII. Conclusion
The research study proposed on determining the type of attacks and their associated
countermeasures helps in analyzing the best suitable model which can be opted for securing
the database premises through the attack on SQL injection. The exploitation of the SQL
query can result in damaging the accuracy of the database because the attacker can
manipulate the information by applying the operation like adding of information, deletion of
information, deletion of information, reading of information and others. The malicious code
and vulnerabilities are sent by the attacker in the SQL statement which exploits and
manipulate the information of the database. The accuracy and integrity of the data stored in
the database can be exploited with the SQLI query posted on the database. During the course
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program, we have analysed various countermeasures and prevention technique for resolving
the problems associated with thee SQL injection program designed by the hacker for
accessing the information from the database. Different mechanisms are applied for predicting
the presence of SQL injection in the query. There are various types of SQL injection used for
hacking such as Tautology, incorrect logic of SQL query, piggy backing SQL injection, and
others. Each type of SQL injection can be resolved by more than one countermeasure. The
most appropriate mode for overcoming the SQL injection problem is the HASH model and
Algorithm procedures. The modification in the query is easily predicted through the
comparison with the hash value stored in the database. The rejection of the hash value helps
in detecting the anomalies associated with the SQL query used for getting authentication of
the user database and account. The algorithm procedures are developed for removing the
SQL injection from the SQL query which is based on Prepared Statement Replacement
procedures. The source code are analysed for removing the association of the malicious code.
The PSR algorithm is used for analysing the attacks through by By-passing the authorisation
and authentication procedures from the Web portal, finger printing attack of the database, use
of UNION query though injection procedure, and many others.
IX. References:
Adhyaru, R. (2016). Techniques for attacking web application security. International journal
of information sciences and techniques, 6 (1/2). Retrieved from
http://aircconline.com/ijist/V6N2/6216ijist05.pdf
Angel, N., and Chandrasekhar, A. (2017). Defence mechanism to avoid SQL injection with
Query filters. International Journal of advanced research in computer science and
software engineering, 6 (10). Retrieved from
http://ijarcsse.com/Before_August_2017/docs/papers/Volume_6/10_October2016/
V6I10-0137.pdf
Clarke, J. (2015). SQL injection attacks and Defense. 1st ed. Retrieved from
https://lira.epac.to/DOCS-TECH/Hacking/SQL%20Injection%20Attacks%20and
%20Defense.pdf

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DB Networks. (2015). SQL injection attacks. 1st ed. Retrieved from
http://www.dbnetworks.com/pdf/sql-injection-detection-web-environment.pdf
Gosnik, D. (2015). A survey on web application vulnerabilities exploitation and security
engine for SQL injection. International conference on communication system and
network topoligies 1st ed. Retrieved from
https://kevincurran.org/com320/papers/WebAppsPaper.pdf
Halde, J. (2008). SQL injection analysis, Detection, and prevention. 1st ed. Retrieved from
http://scholarworks.sjsu.edu/cgi/viewcontent.cgi?article=1081&context=etd_projects
Halfond, W., Viegas, J., and Orso, A. (2015). A classification of SQL injection attacks and
countermeasures. 1st ed. Retrieved from
https://www.cc.gatech.edu/~orso/papers/halfond.viegas.orso.ISSSE06.pdf
Janot, E., and Zavarsky, P. (2015). Preventing SQL injection in Online application. 1st ed.
Retrieved from https://www.owasp.org/images/5/57/OWASP-AppSecEU08-Janot.pdf
Johari, R., and Sharma, P. (2012). A survey on Web application vulnerabilities exploitation
and security engine for SQL injection. International journal on communication
system and Network Topologies. Retrieved
fromhttps://kevincurran.org/com320/papers/WebAppsPaper.pdf
Kindy, D. and Pathan, A. (2012). A detailed survey on various aspects of SQL injection in
web applications: Vulnerabilities, Innovative attacks, and Remedies. 1st ed. Retrieved
from https://arxiv.org/ftp/arxiv/papers/1203/1203.3324.pdf
Morgenroth, S. (2018). SQL injection vulnerabilities and how to prevent them. 1st ed.
Retrieved from https://dzone.com/articles/what-is-the-sql-injection-vulnerability-amp-
how-to
Namdev, M., Hasan, F., and Shrivastav, G. (2012). Review of SQL injection attack and
proposed method of detection and prevention of SQLIA. International journal of
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from
http://ijarcsse.com/Before_August_2017/docs/papers/July2012/Volume_2_issue_7/
V2I700103.pdf
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Qian, L., Zhu, Z., Hu, J., and Liu, S. (2015). Research of SQL injection attack and prevention
technology. 1st ed. Retrieved fromhttps://ieeexplore.ieee.org/document/7280212/
Rua, M., Thiyap, Musab, and Abdulqader. (2017). The impact of SQL injection attacks on the
security of databases. 1st ed. Retrieved from
https://www.researchgate.net/publication/316609616_THE_IMPACT_OF_SQL_INJ
ECTION_ATTACKS_ON_THE_SECURITY_OF_DATABASES
Sajjadi, S., Pour, B. (2013). Study of SQL injection attack. International Journal of computer
and communication engineering, 2(5). Retrieved from
https://pdfs.semanticscholar.org/d896/25e2dc95b1bb42bb89672f5d105c0617ab0f.pdf
Singh, S. ,and Kaur, P. (2015). Extended Security techniques on web application.
International journal of computer science and mobile computing, 4(6). Retrieved
from http://www.ijcsmc.com/docs/papers/June2015/V4I6201599a34.pdf
Tajpour, A., Ibrahim, S., and Masrom, M. (2011). SQL injection detection and prevention
techniques. 1st ed. Retrieved from
https://www.researchgate.net/publication/272854124_SQL_Injection_Detection_and_
Prevention_Techniques
VarunKumar, K., Prabakaran, M., Kaurav, A., Chakkarvarthy, S., Thiyagarajan, S., and
Venkatesh, P. (2014). Various databases attacks and its prevention technique.
International Journal of engineering trends and technology, 9 (11). Retrieved from
http://ijettjournal.org/volume-9/number-11/IJETT-V9P302.pdf
Zhu, Y. (2015). Exploring defense of SQL injection attack in Penetration testing. 1st ed.
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