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SQL injections may happen in any programming language.",{"name":70,"@type":61,"acceptedAnswer":71},"How do parameterized queries (prepared statements) help defend against SQL injection?",{"text":72,"@type":64},"Prepared statements avoid building SQL with string concatenation by using parameters. The library sends user input separately, so SQL commands and data are handled independently, reducing injection risk.","https://schema.org",{"og:url":32,"og:type":75,"og:title":10,"og:site_name":45,"og:description":12},"article",{"robots":77,"canonical":32},"index,follow",{"doc_id":79,"site_id":7},571614,1792086196,{"code":4,"msg":82,"data":83},"success",[84,89,94,99,104,109,114,119,123],{"id":85,"doc_module":22,"doc_module_name":25,"category_name":86,"show_sort_weight":87,"slug":88},11,"Presentations",90,"presentations",{"id":90,"doc_module":22,"doc_module_name":25,"category_name":91,"show_sort_weight":92,"slug":93},12,"Resumes",80,"resumes",{"id":95,"doc_module":22,"doc_module_name":25,"category_name":96,"show_sort_weight":97,"slug":98},14,"Invoices",70,"invoices",{"id":100,"doc_module":22,"doc_module_name":25,"category_name":101,"show_sort_weight":102,"slug":103},15,"Posters",60,"posters",{"id":105,"doc_module":22,"doc_module_name":25,"category_name":106,"show_sort_weight":107,"slug":108},16,"Social Media",50,"social-media",{"id":110,"doc_module":22,"doc_module_name":25,"category_name":111,"show_sort_weight":112,"slug":113},17,"Forms",40,"forms",{"id":115,"doc_module":22,"doc_module_name":25,"category_name":116,"show_sort_weight":117,"slug":118},18,"Letters",30,"letters",{"id":120,"doc_module":22,"doc_module_name":25,"category_name":121,"show_sort_weight":55,"slug":122},21,"Paper Templates","papers-templates",{"id":124,"doc_module":22,"doc_module_name":25,"category_name":29,"show_sort_weight":4,"slug":125},158,"general-158",{"code":4,"msg":82,"data":127},{"doc_id":79,"user_id":128,"nickname":42,"user_avatar":129,"doc_module":22,"category_id":124,"category_name":29,"doc_title":10,"doc_description":12,"doc_content":130,"file_id":131,"file_url":132,"file_type":133,"file_size":134,"view_count":55,"is_deleted":4,"is_public":22,"is_downloadable":22,"audit_status":22,"page_count":22,"language":135,"language_code":8,"site_id":7,"html_lang":8,"table_of_contents":136,"faqs":137,"seo_title":138,"seo_description":12,"update_tm":139,"read_time":4},5909892115043,"https://ap-avatar.wpscdn.com/davatar_6f874abed73319feea01a86fa6f0fab8","SQL Injection Cheat Sheet  \nFOR DEVELOPERS  \nASSUMPTIONS  \nIn this cheat sheet, we will assume that:  \n• You are a developer or you know programming  \n• You have limited web application security knowledge  \n• You need to know how SQL injection attacks happen  \n• You need to know how to fix SQL injection issues in your code  \nGOALS  \nIn this cheat sheet, you will learn:  \n• How do malicious hackers conduct SQL injection attacks  \n• How to fix your code that has SQL injection vulnerabilities  \n• How to avoid SQL injection vulnerabilities for the future  \nP A R T 1 What Are SQL Injection Attacks  \nSQL injections happen when:  \n• Your code uses unsanitized data from user input in SQL statements  \n• A malicious user includes SQL elements in the input in a tricky way  \n• Your code executes these SQL elements as part of legitimate SQL statements  \nSQL INJECTION FAQ  \n• What SQL servers are affected by SQL injections?  \nAll SQL servers may be affected by SQL injections: MySQL, MSSQL, Oracle, PostgreSQL, and more.  \n• What programming languages are affected by SQL injections? SQL injections may happen in any programming language.  \n• What may be the consequences of an SQL injection?  \nAn SQL injection may lead to data leaks but it may also lead to complete system compromise.  \n• How common are SQL injections?  \nIn 2020, SQL injections were found by Acunetix on average in 7% of web apps.  \n• Do web application firewalls (WAF) protect against SQL injections?  \nNo, WAFs only make it more difficult for the attacker to send SQL injection payloads.  \nSIMPLE SQL INJECTION EXAMPLE  \nYOUR CODE IN PHP:  \n\u003C?PHP  \n$userid = $_GET [\"userid\"];  \n$query = \"SELECT user FROM users WHERE userid = $userid;\";$result = pg_query($conn , $query);  \n?>  \nATTACKER REQUEST:  \nYOUR CODE PROCESSES THE FOLLOWING SQL QUERY:  \n$query = \"SELECT user FROM users WHERE userid = 0; DELETE FROM users WHERE 1;\";  \nAs a result, if the current user (current database user) has suitable permissions, the entire users table is cleared.  \nSQL INJECTION TYPES  \nTYPE 1: IN-BAND SQL INJECTION: ERROR-BASED SQL INJECTION  \nattacker  \n• The attacker uses information contained in the error to escalate the attack  \n• This type of SQL injection is used to access sensitive information such as database type, file names, and more  \n• Result: The web application displays the following error in the browser:  \nError: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''' at line 1 Warning: mysql_fetch_array() expects parameter 1 to be resource, boolean given in /hj/var/www/listproducts.php on line 74  \nTYPE 2: IN-BAND SQL INJECTION: UNION-BASED SQL INJECTION  \n• The attacker uses a UNION clause in the payload  \n• The SQL engine combines sensitive information with legitimate information that the web application should display  \n• The web application displays sensitive information  \nEXAMPLE:  \n• Payload:  \n• Result: The web application displays the system version and the name of the current user:  \n8.0.22-0ubuntu[0.20.04.2](0.20.04.2)[ ](0.20.04.2)acuart@localhost  \nTYPE 3: BLIND SQL INJECTION: BOOLEAN-BASED SQL INJECTION  \n• The attacker sends many payloads containing expressions that evaluate to either TRUE or FALSE  \n• Alternating between the two, the attacker can draw conclusions about the database and its contents  \n• This type of SQL injection is often used to access sensitive information when the web application returns neither meaningful error messages nor the targeted data itself  \nTYPE 4: BLIND SQL INJECTION: TIME-BASED SQL INJECTION  \n• If the web application doesn’t return errors and the returned information is the same for boolean-based payloads, the attacker sends a payload that includes a time delay command such as SLEEP, which delays the whole response  \n• The attacker draws conclusions from the length of response delays and repeats the process as many times as necessary with different arguments  \n•","cbCaiaSP6aNDg2YM","https://ap.wps.com/l/cbCaiaSP6aNDg2YM","pdf",303729,"English","# SQL Injection Cheat Sheet\n## Assumptions and Goals\n## What Are SQL Injection Attacks\n## SQL Injection FAQ\n## Simple SQL Injection Example\n## SQL Injection Types\n## SQL Injection Defense\n### Parameterized Queries (Prepared Statements)\n## PHP Example","[{\"question\":\"What key assumption does this cheat sheet make about the reader?\",\"answer\":\"It assumes you are a developer or you know programming, have limited web application security knowledge, and need to understand how SQL injection attacks happen and how to fix them in code.\"},{\"question\":\"Which SQL servers and programming languages can be affected by SQL injections?\",\"answer\":\"SQL injections may affect all SQL servers, including MySQL, MSSQL, Oracle, PostgreSQL, and others. SQL injections may happen in any programming language.\"},{\"question\":\"How do parameterized queries (prepared statements) help defend against SQL injection?\",\"answer\":\"Prepared statements avoid building SQL with string concatenation by using parameters. The library sends user input separately, so SQL commands and data are handled independently, reducing injection risk.\"}]","SQL Injection Cheat Sheet - For Developers - How SQL Injection Works and How to Fix It | PDF",1791922737]