SQL injection vulnerabilities arise when user-controllable data is incorporated into database SQL queries in an unsafe manner. An attacker can supply crafted input to break out of the data context in which their input appears and interfere with the structure of the surrounding query.
Various attacks can be delivered via SQL injection, including reading or modifying critical application data, interfering with application logic, escalating privileges within the database and executing operating system commands.
Remediation background
The most effective way to prevent SQL injection attacks is to use parameterised queries (also known as prepared statements) for all database access. This method uses two steps to incorporate potentially tainted data into SQL queries: first, the application specifies the structure of the query, leaving placeholders for each item of user input; second, the application specifies the contents of each placeholder. Because the structure of the query has already defined in the first step, it is not possible for malformed data in the second step to interfere with the query structure. You should review the documentation for your database and application platform to determine the appropriate APIs which you can use to perform parameterised queries. It is strongly recommended that you parameterise every variable data item that is incorporated into database queries, even if it is not obviously tainted, to prevent oversights occurring and avoid vulnerabilities being introduced by changes elsewhere within the code base of the application.
You should be aware that some commonly employed and recommended mitigations for SQL injection vulnerabilities are not always effective:
One common defence is to double up any single quotation marks appearing within user input before incorporating that input into a SQL query. This defence is designed to prevent malformed data from terminating the string in which it is inserted. However, if the data being incorporated into queries is numeric, then the defence may fail, because numeric data may not be encapsulated within quotes, in which case only a space is required to break out of the data context and interfere with the query. Further, in second-order SQL injection attacks, data that has been safely escaped when initially inserted into the database is subsequently read from the database and then passed back to it again. Quotation marks that have been doubled up initially will return to their original form when the data is reused, allowing the defence to be bypassed.
Another often cited defence is to use stored procedures for database access. While stored procedures can provide security benefits, they are not guaranteed to prevent SQL injection attacks. The same kinds of vulnerabilities that arise within standard dynamic SQL queries can arise if any SQL is dynamically constructed within stored procedures. Further, even if the procedure is sound, SQL injection can arise if the procedure is invoked in an unsafe manner using user-controllable data.
The queryString parameter appears to be vulnerable to SQL injection attacks. The payload %00' was submitted in the queryString parameter, and a database error message was returned. You should review the contents of the error message, and the application's handling of other input, to confirm whether a vulnerability is present.
The database appears to be PostgreSQL.
The application attempts to block SQL injection attacks but this can be circumvented by submitting a URL-encoded NULL byte (%00) before the characters that are being blocked.
Remediation detail
The application should handle errors gracefully and prevent SQL error messages from being returned in responses. NULL byte bypasses typically arise when the application is being defended by a web application firewall (WAF) that is written in native code, where strings are terminated by a NULL byte. You should fix the actual vulnerability within the application code, and if appropriate ask your WAF vendor to provide a fix for the NULL byte bypass.
The REST URL parameter 7 appears to be vulnerable to SQL injection attacks. The payload ' was submitted in the REST URL parameter 7, and a database error message was returned. You should review the contents of the error message, and the application's handling of other input, to confirm whether a vulnerability is present.
The database appears to be PostgreSQL.
Remediation detail
The application should handle errors gracefully and prevent SQL error messages from being returned in responses.
HTTP/1.1 500 Internal Server Error Vary: Accept-Encoding Cache-Control: max-age=3600 Content-Type: text/html;charset=ISO-8859-1 Date: Wed, 09 Nov 2011 13:03:52 GMT Connection: close X-xgen-cache: yes X-Cache-Info: not cacheable; response code not cacheable
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF ...[SNIP]... <br>
The REST URL parameter 8 appears to be vulnerable to SQL injection attacks. The payload ' was submitted in the REST URL parameter 8, and a database error message was returned. You should review the contents of the error message, and the application's handling of other input, to confirm whether a vulnerability is present.
The database appears to be PostgreSQL.
Remediation detail
The application should handle errors gracefully and prevent SQL error messages from being returned in responses.
HTTP/1.1 500 Internal Server Error Vary: Accept-Encoding Cache-Control: max-age=3600 Content-Type: text/html;charset=ISO-8859-1 Date: Wed, 09 Nov 2011 13:03:54 GMT Connection: close X-xgen-cache: yes X-Cache-Info: not cacheable; response code not cacheable
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF ...[SNIP]... <br>
The spaceKey parameter appears to be vulnerable to SQL injection attacks. The payload %00' was submitted in the spaceKey parameter, and a database error message was returned. You should review the contents of the error message, and the application's handling of other input, to confirm whether a vulnerability is present.
The database appears to be PostgreSQL.
The application attempts to block SQL injection attacks but this can be circumvented by submitting a URL-encoded NULL byte (%00) before the characters that are being blocked.
Remediation detail
The application should handle errors gracefully and prevent SQL error messages from being returned in responses. NULL byte bypasses typically arise when the application is being defended by a web application firewall (WAF) that is written in native code, where strings are terminated by a NULL byte. You should fix the actual vulnerability within the application code, and if appropriate ask your WAF vendor to provide a fix for the NULL byte bypass.
The spaceKey parameter appears to be vulnerable to SQL injection attacks. The payload %00' was submitted in the spaceKey parameter, and a database error message was returned. You should review the contents of the error message, and the application's handling of other input, to confirm whether a vulnerability is present.
The database appears to be PostgreSQL.
The application attempts to block SQL injection attacks but this can be circumvented by submitting a URL-encoded NULL byte (%00) before the characters that are being blocked.
Remediation detail
The application should handle errors gracefully and prevent SQL error messages from being returned in responses. NULL byte bypasses typically arise when the application is being defended by a web application firewall (WAF) that is written in native code, where strings are terminated by a NULL byte. You should fix the actual vulnerability within the application code, and if appropriate ask your WAF vendor to provide a fix for the NULL byte bypass.
The spaceKey parameter appears to be vulnerable to SQL injection attacks. The payload %00' was submitted in the spaceKey parameter, and a database error message was returned. You should review the contents of the error message, and the application's handling of other input, to confirm whether a vulnerability is present.
The database appears to be PostgreSQL.
The application attempts to block SQL injection attacks but this can be circumvented by submitting a URL-encoded NULL byte (%00) before the characters that are being blocked.
Remediation detail
The application should handle errors gracefully and prevent SQL error messages from being returned in responses. NULL byte bypasses typically arise when the application is being defended by a web application firewall (WAF) that is written in native code, where strings are terminated by a NULL byte. You should fix the actual vulnerability within the application code, and if appropriate ask your WAF vendor to provide a fix for the NULL byte bypass.
The spaceKey parameter appears to be vulnerable to SQL injection attacks. The payload %00' was submitted in the spaceKey parameter, and a database error message was returned. You should review the contents of the error message, and the application's handling of other input, to confirm whether a vulnerability is present.
The database appears to be PostgreSQL.
The application attempts to block SQL injection attacks but this can be circumvented by submitting a URL-encoded NULL byte (%00) before the characters that are being blocked.
Remediation detail
The application should handle errors gracefully and prevent SQL error messages from being returned in responses. NULL byte bypasses typically arise when the application is being defended by a web application firewall (WAF) that is written in native code, where strings are terminated by a NULL byte. You should fix the actual vulnerability within the application code, and if appropriate ask your WAF vendor to provide a fix for the NULL byte bypass.
The spaceKey parameter appears to be vulnerable to SQL injection attacks. The payload %00' was submitted in the spaceKey parameter, and a database error message was returned. You should review the contents of the error message, and the application's handling of other input, to confirm whether a vulnerability is present.
The database appears to be PostgreSQL.
The application attempts to block SQL injection attacks but this can be circumvented by submitting a URL-encoded NULL byte (%00) before the characters that are being blocked.
Remediation detail
The application should handle errors gracefully and prevent SQL error messages from being returned in responses. NULL byte bypasses typically arise when the application is being defended by a web application firewall (WAF) that is written in native code, where strings are terminated by a NULL byte. You should fix the actual vulnerability within the application code, and if appropriate ask your WAF vendor to provide a fix for the NULL byte bypass.
Reflected cross-site scripting vulnerabilities arise when data is copied from a request and echoed into the application's immediate response in an unsafe way. An attacker can use the vulnerability to construct a request which, if issued by another application user, will cause JavaScript code supplied by the attacker to execute within the user's browser in the context of that user's session with the application.
The attacker-supplied code can perform a wide variety of actions, such as stealing the victim's session token or login credentials, performing arbitrary actions on the victim's behalf, and logging their keystrokes.
Users can be induced to issue the attacker's crafted request in various ways. For example, the attacker can send a victim a link containing a malicious URL in an email or instant message. They can submit the link to popular web sites that allow content authoring, for example in blog comments. And they can create an innocuous looking web site which causes anyone viewing it to make arbitrary cross-domain requests to the vulnerable application (using either the GET or the POST method).
The security impact of cross-site scripting vulnerabilities is dependent upon the nature of the vulnerable application, the kinds of data and functionality which it contains, and the other applications which belong to the same domain and organisation. If the application is used only to display non-sensitive public content, with no authentication or access control functionality, then a cross-site scripting flaw may be considered low risk. However, if the same application resides on a domain which can access cookies for other more security-critical applications, then the vulnerability could be used to attack those other applications, and so may be considered high risk. Similarly, if the organisation which owns the application is a likely target for phishing attacks, then the vulnerability could be leveraged to lend credibility to such attacks, by injecting Trojan functionality into the vulnerable application, and exploiting users' trust in the organisation in order to capture credentials for other applications which it owns. In many kinds of application, such as those providing online banking functionality, cross-site scripting should always be considered high risk.
Issue remediation
In most situations where user-controllable data is copied into application responses, cross-site scripting attacks can be prevented using two layers of defences:
Input should be validated as strictly as possible on arrival, given the kind of content which it is expected to contain. For example, personal names should consist of alphabetical and a small range of typographical characters, and be relatively short; a year of birth should consist of exactly four numerals; email addresses should match a well-defined regular expression. Input which fails the validation should be rejected, not sanitised.
User input should be HTML-encoded at any point where it is copied into application responses. All HTML metacharacters, including < > " ' and =, should be replaced with the corresponding HTML entities (< > etc).
In cases where the application's functionality allows users to author content using a restricted subset of HTML tags and attributes (for example, blog comments which allow limited formatting and linking), it is necessary to parse the supplied HTML to validate that it does not use any dangerous syntax; this is a non-trivial task.
The value of the query request parameter is copied into the HTML document as plain text between tags. The payload bc92f<img%20src%3da%20onerror%3dalert(1)>204bb8686be was submitted in the query parameter. This input was echoed as bc92f<img src=a onerror=alert(1)>204bb8686be in the application's response.
This proof-of-concept attack demonstrates that it is possible to inject arbitrary JavaScript into the application's response. The PoC attack demonstrated uses an event handler to introduce arbitrary JavaScript into the document.
The value of the spaceKey request parameter is copied into the HTML document as plain text between tags. The payload ee2fc<script>alert(1)</script>34ff8fd4c03 was submitted in the spaceKey parameter. This input was echoed unmodified in the application's response.
This proof-of-concept attack demonstrates that it is possible to inject arbitrary JavaScript into the application's response.
Sensitive information within URLs may be logged in various locations, including the user's browser, the web server, and any forward or reverse proxy servers between the two endpoints. URLs may also be displayed on-screen, bookmarked or emailed around by users. They may be disclosed to third parties via the Referer header when any off-site links are followed. Placing session tokens into the URL increases the risk that they will be captured by an attacker.
Issue remediation
The application should use an alternative mechanism for transmitting session tokens, such as HTTP cookies or hidden fields in forms that are submitted using the POST method.
If the HttpOnly attribute is set on a cookie, then the cookie's value cannot be read or set by client-side JavaScript. This measure can prevent certain client-side attacks, such as cross-site scripting, from trivially capturing the cookie's value via an injected script.
Issue remediation
There is usually no good reason not to set the HttpOnly flag on all cookies. Unless you specifically require legitimate client-side scripts within your application to read or set a cookie's value, you should set the HttpOnly flag by including this attribute within the relevant Set-cookie directive.
You should be aware that the restrictions imposed by the HttpOnly flag can potentially be circumvented in some circumstances, and that numerous other serious attacks can be delivered by client-side script injection, aside from simple cookie stealing.
The following cookie was issued by the application and does not have the HttpOnly flag set:
rack.session=BAh7AA%3D%3D%0A; path=/
The cookie appears to contain a session token, which may increase the risk associated with this issue. You should review the contents of the cookie to determine its function.
The following cookie was issued by the application and does not have the HttpOnly flag set:
rack.session=BAh7AA%3D%3D%0A; path=/
The cookie appears to contain a session token, which may increase the risk associated with this issue. You should review the contents of the cookie to determine its function.
The following cookie was issued by the application and does not have the HttpOnly flag set:
rack.session=BAh7AA%3D%3D%0A; path=/
The cookie appears to contain a session token, which may increase the risk associated with this issue. You should review the contents of the cookie to determine its function.
The following cookie was issued by the application and does not have the HttpOnly flag set:
rack.session=BAh7AA%3D%3D%0A; path=/
The cookie appears to contain a session token, which may increase the risk associated with this issue. You should review the contents of the cookie to determine its function.
The following cookie was issued by the application and does not have the HttpOnly flag set:
rack.session=BAh7AA%3D%3D%0A; path=/
The cookie appears to contain a session token, which may increase the risk associated with this issue. You should review the contents of the cookie to determine its function.
The following cookie was issued by the application and does not have the HttpOnly flag set:
rack.session=BAh7AA%3D%3D%0A; path=/
The cookie appears to contain a session token, which may increase the risk associated with this issue. You should review the contents of the cookie to determine its function.
The following cookie was issued by the application and does not have the HttpOnly flag set:
rack.session=BAh7AA%3D%3D%0A; path=/
The cookie appears to contain a session token, which may increase the risk associated with this issue. You should review the contents of the cookie to determine its function.
The following cookie was issued by the application and does not have the HttpOnly flag set:
rack.session=BAh7AA%3D%3D%0A; path=/
The cookie appears to contain a session token, which may increase the risk associated with this issue. You should review the contents of the cookie to determine its function.
The following cookie was issued by the application and does not have the HttpOnly flag set:
rack.session=BAh7AA%3D%3D%0A; path=/
The cookie appears to contain a session token, which may increase the risk associated with this issue. You should review the contents of the cookie to determine its function.
The cookie does not appear to contain a session token, which may reduce the risk associated with this issue. You should review the contents of the cookie to determine its function.
Request
GET / HTTP/1.1 Host: www.mongodb.org User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.2.13) Gecko/20110504 Namoroka/3.6.13 Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8 Accept-Language: en-us,en;q=0.5 Accept-Encoding: gzip,deflate Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7 Keep-Alive: 115 Proxy-Connection: keep-alive Referer: http://www.mongodb.com/
The application's responses appear to depend systematically on the presence or absence of the Referer header in requests. This behaviour does not necessarily constitute a security vulnerability, and you should investigate the nature of and reason for the differential responses to determine whether a vulnerability is present.
Common explanations for Referer-dependent responses include:
Referer-based access controls, where the application assumes that if you have arrived from one privileged location then you are authorised to access another privileged location. These controls can be trivially defeated by supplying an accepted Referer header in requests for the vulnerable function.
Attempts to prevent cross-site request forgery attacks by verifying that requests to perform privileged actions originated from within the application itself and not from some external location. Such defences are not robust - methods have existed through which an attacker can forge or mask the Referer header contained within a target user's requests, by leveraging client-side technologies such as Flash and other techniques.
Delivery of Referer-tailored content, such as welcome messages to visitors from specific domains, search-engine optimisation (SEO) techniques, and other ways of tailoring the user's experience. Such behaviours often have no security impact; however, unsafe processing of the Referer header may introduce vulnerabilities such as SQL injection and cross-site scripting. If parts of the document (such as META keywords) are updated based on search engine queries contained in the Referer header, then the application may be vulnerable to persistent code injection attacks, in which search terms are manipulated to cause malicious content to appear in responses served to other application users.
Issue remediation
The Referer header is not a robust foundation on which to build any security measures, such as access controls or defences against cross-site request forgery. Any such measures should be replaced with more secure alternatives that are not vulnerable to Referer spoofing.
If the contents of responses is updated based on Referer data, then the same defences against malicious input should be employed here as for any other kinds of user-supplied data.
HTTP/1.1 500 Internal Server Error Vary: Accept-Encoding Cache-Control: max-age=3600 Content-Type: text/html;charset=ISO-8859-1 Date: Wed, 09 Nov 2011 13:19:29 GMT Connection: close X-xgen-cache: yes X-Cache-Info: not cacheable; response code not cacheable
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF ...[SNIP]... <p>http://burp/show/5</p>
HTTP/1.1 500 Internal Server Error Vary: Accept-Encoding Cache-Control: max-age=3600 Content-Type: text/html;charset=ISO-8859-1 Date: Wed, 09 Nov 2011 13:19:42 GMT Connection: close X-xgen-cache: yes X-Cache-Info: not cacheable; response code not cacheable
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF ...[SNIP]... <p>Unknown</p>
When a web browser makes a request for a resource, it typically adds an HTTP header, called the "Referer" header, indicating the URL of the resource from which the request originated. This occurs in numerous situations, for example when a web page loads an image or script, or when a user clicks on a link or submits a form.
If the resource being requested resides on a different domain, then the Referer header is still generally included in the cross-domain request. If the originating URL contains any sensitive information within its query string, such as a session token, then this information will be transmitted to the other domain. If the other domain is not fully trusted by the application, then this may lead to a security compromise.
You should review the contents of the information being transmitted to other domains, and also determine whether those domains are fully trusted by the originating application.
Today's browsers may withhold the Referer header in some situations (for example, when loading a non-HTTPS resource from a page that was loaded over HTTPS, or when a Refresh directive is issued), but this behaviour should not be relied upon to protect the originating URL from disclosure.
Note also that if users can author content within the application then an attacker may be able to inject links referring to a domain they control in order to capture data from URLs used within the application.
Issue remediation
The application should never transmit any sensitive information within the URL query string. In addition to being leaked in the Referer header, such information may be logged in various locations and may be visible on-screen to untrusted parties.
HTTP/1.1 500 Internal Server Error Vary: Accept-Encoding Cache-Control: max-age=3600 Content-Type: text/html;charset=ISO-8859-1 Date: Wed, 09 Nov 2011 13:19:29 GMT Connection: close X-xgen-cache: yes X-Cache-Info: not cacheable; response code not cacheable
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF ...[SNIP]... <strong><a href="http://support.atlassian.com">Atlassian's support system</a></strong> at <a href="http://support.atlassian.com">http://support.atlassian.com</a> ...[SNIP]...
7. Cross-domain script includepreviousnext There are 3 instances of this issue:
When an application includes a script from an external domain, this script is executed by the browser within the security context of the invoking application. The script can therefore do anything that the application's own scripts can do, such as accessing application data and performing actions within the context of the current user.
If you include a script from an external domain, then you are trusting that domain with the data and functionality of your application, and you are trusting the domain's own security to prevent an attacker from modifying the script to perform malicious actions within your application.
Issue remediation
Scripts should not be included from untrusted domains. If you have a requirement which a third-party script appears to fulfil, then you should ideally copy the contents of that script onto your own domain and include it from there. If that is not possible (e.g. for licensing reasons) then you should consider reimplementing the script's functionality within your own code.
The TRACE method is designed for diagnostic purposes. If enabled, the web server will respond to requests which use the TRACE method by echoing in its response the exact request which was received.
Although this behaviour is apparently harmless in itself, it can sometimes be leveraged to support attacks against other application users. If an attacker can find a way of causing a user to make a TRACE request, and can retrieve the response to that request, then the attacker will be able to capture any sensitive data which is included in the request by the user's browser, for example session cookies or credentials for platform-level authentication. This may exacerbate the impact of other vulnerabilities, such as cross-site scripting.
Issue remediation
The TRACE method should be disabled on the web server.
The presence of email addresses within application responses does not necessarily constitute a security vulnerability. Email addresses may appear intentionally within contact information, and many applications (such as web mail) include arbitrary third-party email addresses within their core content.
However, email addresses of developers and other individuals (whether appearing on-screen or hidden within page source) may disclose information that is useful to an attacker; for example, they may represent usernames that can be used at the application's login, and they may be used in social engineering attacks against the organisation's personnel. Unnecessary or excessive disclosure of email addresses may also lead to an increase in the volume of spam email received.
Issue remediation
You should review the email addresses being disclosed by the application, and consider removing any that are unnecessary, or replacing personal addresses with anonymous mailbox addresses (such as helpdesk@example.com).
HTTP/1.1 200 OK Vary: Accept-Encoding Cache-Control: max-age=3600 Content-Type: application/x-javascript;charset=UTF-8 Date: Wed, 09 Nov 2011 13:03:20 GMT Expires: Sat, 06 Nov 2021 13:03:20 GMT ETag: "1320755916000" X-xgen-cache: yes Last-Modified: Tue, 08 Nov 2011 12:38:36 GMT X-Cache-Info: caching Content-Length: 3598
jQuery.noConflict(); /* Copyright (c) 2007 Paul Bakaus (paul.bakaus@googlemail.com) and Brandon Aaron (brandon.aaron@gmail.com || http://brandonaaron.net) * Dual licensed under the MIT (http://www.opensource.org/licenses/mit-license.php) * and GPL (http://www.opensource.org/licenses/gpl-license.php) licenses. * * $LastCha ...[SNIP]...
HTTP/1.1 200 OK Vary: Accept-Encoding Cache-Control: max-age=3600 Content-Type: application/x-javascript;charset=UTF-8 Date: Wed, 09 Nov 2011 13:03:20 GMT Expires: Sat, 06 Nov 2021 13:03:20 GMT ETag: "1320755916000" X-xgen-cache: yes Last-Modified: Tue, 08 Nov 2011 12:38:36 GMT X-Cache-Info: caching Content-Length: 37808
/* Prototype JavaScript framework, version 1.4.0_pre11 * (c) 2005 Sam Stephenson <sam@conio.net> * * THIS FILE IS AUTOMATICALLY GENERATED. When sending patches, please diff * against the sourc ...[SNIP]...
10. Content type incorrectly statedprevious There are 3 instances of this issue:
If a web response specifies an incorrect content type, then browsers may process the response in unexpected ways. If the specified content type is a renderable text-based format, then the browser will usually attempt to parse and render the response in that format. If the specified type is an image format, then the browser will usually detect the anomaly and will analyse the actual content and attempt to determine its MIME type. Either case can lead to unexpected results, and if the content contains any user-controllable data may lead to cross-site scripting or other client-side vulnerabilities.
In most cases, the presence of an incorrect content type statement does not constitute a security flaw, particularly if the response contains static content. You should review the contents of the response and the context in which it appears to determine whether any vulnerability exists.
Issue remediation
For every response containing a message body, the application should include a single Content-type header which correctly and unambiguously states the MIME type of the content in the response body.