Improper Sanitization of Script-Related HTML Tags in a Web Page (Basic XSS) |
Weakness ID: 80 (Weakness Variant) | Status: Incomplete |
Description Summary
Extended Description
This may allow such characters to be treated as control characters, which are executed client-side in the context of the user's session. Although this can be classified as an injection problem, the more pertinent issue is the failure to convert such special characters to respective context-appropriate entities before displaying them to the user.
Example 1
In the following example, a guestbook comment isn't properly sanitized for script-related tags before being displayed in a client browser.
Reference | Description |
---|---|
CVE-2002-0938 | XSS in parameter in a link. |
CVE-2002-1495 | XSS in web-based email product via attachment filenames. |
CVE-2003-1136 | HTML injection in posted message. |
CVE-2004-2171 | XSS not quoted in error page. |
Carefully check each input parameter against a rigorous positive specification (white list) defining the specific characters and format allowed. All input should be sanitized, not just parameters that the user is supposed to specify, but all data in the request, including hidden fields, cookies, headers, the URL itself, and so forth. A common mistake that leads to continuing XSS vulnerabilities is to validate only fields that are expected to be redisplayed by the site. We often encounter data from the request that is reflected by the application server or the application that the development team did not anticipate. Also, a field that is not currently reflected may be used by a future developer. Therefore, validating ALL parts of the HTTP request is recommended. |
This involves "HTML Entity Encoding" all non-alphanumeric characters from data that was received from the user and is now being written to the request. |
With Struts, you should write all data from form beans with the bean's filter attribute set to true. |
Additionally, to help mitigate XSS attacks against the user's session cookie, set the session cookie to be HttpOnly. In browsers that support the HttpOnly feature (such as Internet Explorer), this attribute prevents the user's session cookie from being accessed by client-side scripts, including scripts inserted due to a XSS attack. |
Ordinality | Description |
---|---|
Primary | (where the weakness exists independent of other weaknesses) |
Nature | Type | ID | Name | View(s) this relationship pertains to |
---|---|---|---|---|
ChildOf | Weakness Base | 79 | Failure to Preserve Web Page Structure ('Cross-site Scripting') | Development Concepts (primary)699 Research Concepts (primary)1000 |
MemberOf | View | 630 | Weaknesses Examined by SAMATE | Weaknesses Examined by SAMATE (primary)630 |
CAPEC-ID | Attack Pattern Name | (CAPEC Version: 1.4) |
---|---|---|
18 | Embedding Scripts in Nonscript Elements |
A weakness where the code path has: 1. start statement that accepts input from HTML page 2. end statement that publishes a data item to HTML where a. the input is part of the data item and b. the input contains XSS syntax |
Submissions | ||||
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Submission Date | Submitter | Organization | Source | |
PLOVER | Externally Mined | |||
Modifications | ||||
Modification Date | Modifier | Organization | Source | |
2008-07-01 | Sean Eidemiller | Cigital | External | |
added/updated demonstrative examples | ||||
2008-07-01 | Eric Dalci | Cigital | External | |
updated Time of Introduction | ||||
2008-08-01 | KDM Analytics | External | ||
added/updated white box definitions | ||||
2008-09-08 | CWE Content Team | MITRE | Internal | |
updated Relationships, Taxonomy Mappings, Weakness Ordinalities | ||||
2008-10-14 | CWE Content Team | MITRE | Internal | |
updated Description | ||||
2009-05-27 | CWE Content Team | MITRE | Internal | |
updated Demonstrative Examples, Description, Name | ||||
2009-07-17 | KDM Analytics | External | ||
Improved the White Box Definition | ||||
2009-07-27 | CWE Content Team | MITRE | Internal | |
updated White Box Definitions | ||||
Previous Entry Names | ||||
Change Date | Previous Entry Name | |||
2008-04-11 | Basic XSS | |||
2009-05-27 | Failure to Sanitize Script-Related HTML Tags in a Web Page (Basic XSS) | |||