SQL Injection occurs when data input for example by a user is interpreted as a SQL command rather than normal data by the backend database. This is an extremely common vulnerability and its successful exploitation can have critical implications. Netsparker confirmed the vulnerability by executing a test SQL Query on the back-end database. In these tests, SQL Injection was not obvious but the different responses from the page based on the injection test allowed us to identify and confirm the SQL Injection.
Impact
Depending on the backend database, the database connection settings and the operating system, an attacker can mount one or more of the following type of attacks successfully:
Reading, Updating and Deleting arbitrary data from the database
Executing commands on the underlying operating system
Reading, Updating and Deleting arbitrary tables from the database
Actions to Take
See the remedy for solution.
If you are not using a database access layer (DAL), consider using one. This will help you to centralise the issue. You can also use an ORM (object relational mapping). Most of the ORM systems use only parameterised queries and this can solve the whole SQL Injection problem.
Locate the all dynamically generated SQL queries and convert them to parameterised queries. (If you decide to use a DAL/ORM change all legacy code to use these new libraries)
Use your weblogs and application logs to see if there was any previous but undetected attack to this resource.
Remedy
A robust method for mitigating the threat of SQL Injection based vulnerabilities is to use parameterized queries (prepared statements). Almost all modern languages provide built in libraries for this. Wherever possible do not create dynamic SQL queries or SQL queries with string concatenation.
Required Skills for Successful Exploitation
There are numerous freely available tools to exploit SQL Injection vulnerabilities. This is a complex area with many dependencies, however it should be noted that the numerous resources available in this area have raised both attacker awareness of the issues and their ability to discover and leverage them. SQL Injection is one of the most common web application vulnerabilities.
SQL Injection occurs when data input for example by a user is interpreted as a SQL command rather than normal data by the backend database. This is an extremely common vulnerability and its successful exploitation can have critical implications. Netsparker confirmed the vulnerability by executing a test SQL Query on the back-end database. In these tests, SQL Injection was not obvious but the different responses from the page based on the injection test allowed Netsparker to identify and confirm the SQL Injection.
Impact
Depending on the backend database, the database connection settings and the operating system, an attacker can mount one or more of the following type of attacks successfully:
Reading, Updating and Deleting arbitrary data from the database
Executing commands on the underlying operating system
Reading, Updating and Deleting arbitrary tables from the database
Actions to Take
See the remedy for solution.
If you are not using a database access layer (DAL), consider using one. This will help you to centralise the issue. You can also use an ORM (object relational mapping). Most of the ORM systems use only parameterised queries and this can solve the whole SQL Injection problem.
Locate all of the dynamically generated SQL queries and convert them to parameterised queries. (If you decide to use a DAL/ORM change all legacy code to use these new libraries)
Use your weblogs and application logs to see if there was any previous but undetected attack to this resource.
Remedy
The best way to protect your code against SQL Injections is using parameterised queries (prepared statements). Almost all modern languages provide built in libraries for this. Wherever possible do not create dynamic SQL queries or SQL queries with string concatenation.
Required Skills for Successful Exploitation
There are numerous freely available tools to exploit SQL Injection vulnerabilities. This is a complex area with many dependencies, however it should be noted that the numerous resources available in this area have raised both attacker awareness of the issues and their ability to discover and leverage them.
XSS (Cross-site Scripting) allows an attacker to execute a dynamic script (Javascript, VbScript) in the context of the application. This allows several different attack opportunities, mostly hijacking the current session of the user or changing the look of the page by changing the HTML on the fly to steal the user's credentials. This happens because the input entered by a user has been interpreted as HTML/Javascript/VbScript by the browser.
XSS targets the users of the application instead of the server. Although this is a limitation, since it allows attackers to hijack other users' session, an attacker might attack an administrator to gain full control over the application.
Impact
There are many different attacks that can be leveraged through the use of XSS, including:
Hi-jacking users' active session
Changing the look of the page within the victims browser.
Mounting a successful phishing attack.
Intercept data and perform man-in-the-middle attacks.
Remedy
The issue occurs because the browser interprets the input as active HTML, Javascript or VbScript. To avoid this, all input and output from the application should be filtered. Output should be filtered according to the output format and location. Typically the output location is HTML. Where the output is HTML ensure that all active content is removed prior to its presentation to the server.
Prior to sanitizing user input, ensure you have a pre-defined list of both expected and acceptable characters with which you populate a white-list. This list needs only be defined once and should be used to sanitize and validate all subsequent input.
There are a number of pre-defined, well structured white-list libraries available for many different environments, good examples of these include, OWASP Reform and Microsoft Anti Cross-site Scripting libraries are good examples.
Netsparker identified that the target web site is connecting to the backend database by using a user that has administrative privileges. This issue has been confirmed by checking the connection privileges via an identified SQL Injection vulnerability in the application.
Impact
This can allow an attacker to gain extra privileges via SQL Injection attacks. Here is the list of attacks that the attacker might carry out:
Gain full access to the database server.
Gain a reverse shell to the database server and execute commands on the underlying operating system.
Access the database with full permissions. Where it may be possible to read, update or delete arbitrary data from the database.
Furthermore, depending on the platform and the database system user an attacker might carry out a privilege escalation attack to gain administrator access to the target system.
Remedy
Create a database user with the least possible permissions for your application and connect to the database with that user. Always follow the principle of providing the least privileges for all users and applications.
Netsparker identified that the target web server is an Apache server. This was disclosed through the HTTP response. This information can help an attacker to gain a greater understanding of the systems in use and potentially develop further attacks targeted at the specific version of Apache.
Impact
An attacker can search for specific security vulnerabilities for the version of Apache identified within the SERVER header.
Remedy
Configure your web server to prevent information leakage from the SERVER header of its HTTP response.
Netsparker identified that the target web server is disclosing the PHP version in use through the HTTP response. This information can help an attacker to gain a greater understanding of the systems in use and potentially develop further attacks targeted at the specific version of PHP.
Impact
An attacker can look for specific security vulnerabilities for the version identified. Also the attacker can use this information in conjunction with the other vulnerabilities in the application or the web server.
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN"><html><head><title>403 Forbidden</title></head><body><h1>Forbidden</h1><p>You don't have permission to access /on this server.</p><hr><address>Apache/2.2.14 (Ubuntu) Server at w.sharethis.com Port 80</address></body></html>
Netsparker identified that the target web site is using a MySQL Server. This is generally not a security issue and is reported here for information purposes.
Impact
This issue is reported as additional information only, there is no direct impact arising from this issue.
