[Joel (aspire488)]

Description

Tests and Documentation

Summary

Adds XXE output detection for XML XInclude elements that reference external resources.

Changes

• Detects prefixed and unprefixed XInclude elements with external href values using file:, http:, https:, or ftp: schemes.
• Adds positive test cases for local-file and remote-resource references.
• Adds negative test cases for relative references and unrelated XML elements to reduce false positives.

Testing

• Regex smoke tests passed for local-file references, remote URLs, relative references, unrelated XML elements, and unprefixed include elements.
• The full PyRIT test suite has not yet been run.

Scope

This change addresses the XInclude detection gap discussed in #3324. It complements existing XXE-related coverage without changing unrelated detection behavior.

[Richard Lundeen (richlundeen)]

This pattern is broader than XInclude. It matches an ordinary <include href="https://example.com/help.xml" /> with no XInclude namespace, and it also matches <xi:include data-href="https://example.com/help.xml" /> even though that element has no href attribute. Both now count as successful XXE output.

Please narrow the match and add these negative cases. If recognizing XInclude correctly needs substantially more XML parsing machinery, I would rather close this small extension than add that complexity to a regex scorer.

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