Python: Extend InMemoryCollection filter attribute blocklist

[moonbox3]

Summary

• Minor defense-in-depth hardening for InMemoryCollection filter parsing.
• Extends the internal dunder attribute blocklist and adds a regression test covering the blocked set.

Test plan

• uv run pytest tests/unit/connectors/memory/test_in_memory.py

[github-actions]

Automated Code Review

Reviewers: 4 | Confidence: 93% | Result: All clear

Reviewed: Correctness, Security Reliability, Test Coverage, Design Approach

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Automated review by moonbox3's agents

[Copilot]

Pull request overview

Hardens InMemoryCollection’s string-filter sandboxing by expanding the blocked attribute set and adding a regression test to ensure common introspection/function-internals dunder attributes are rejected during filter parsing.

Changes:

• Add __base__ to the blocked_filter_attributes set used by the in-memory filter validator/evaluator.
• Add a parametrized unit test asserting several dangerous dunder attributes are rejected with a clear error.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
python/semantic_kernel/connectors/in_memory.py	Extends the filter attribute blocklist to include __base__ (defense-in-depth against sandbox escape chains).
python/tests/unit/connectors/memory/test_in_memory.py	Adds regression coverage to ensure key blocked dunder attributes are consistently rejected.

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[moonbox3]

Python Test Coverage Report •

File	Stmts	Miss	Cover	Missing
connectors
in_memory.py	401	135	66%	67–70, 74, 78–81, 97, 101, 107–108, 138, 147, 155, 161, 167–168, 178–179, 183–186, 195–196, 200–201, 205–211, 215–229, 235–238, 258, 260, 263–268, 270, 279–282, 285, 290–292, 296–297, 302, 307, 315–333, 339–347, 354, 356, 359, 366, 381–382, 385, 390, 401–402, 405, 409, 614, 626, 628, 669, 673, 677, 692, 709, 724, 751, 771, 777, 790, 818, 823, 832, 845, 866, 901
TOTAL	28578	5647	80%

Python Unit Test Overview

Tests	Skipped	Failures	Errors	Time
3874	23 💤	0 ❌	0 🔥	1m 53s ⏱️