Fix analyze_db size bypass for dynamic payloads

[keyanskv]

Adds payload_cached_size to module metadata cache to allow is_payload_compatible? to correctly reject large payloads with dynamic sizes.

Description

This change adds payload_cached_size to the module metadata cache so that is_payload_compatible? can make payload size decisions without loading the payload module.

Previously, payloads with dynamic sizes could not always be evaluated correctly from cached metadata alone. As a result, oversized payloads could pass compatibility checks because the cached metadata did not include the information needed to determine their effective size.

With this change:

• payload_cached_size is stored in the module metadata cache.

• is_payload_compatible? uses the cached size information when performing compatibility checks.

• Dynamic payloads with cached size metadata are correctly rejected when they exceed the exploit's available payload space.

• Existing behavior for static payloads remains unchanged.

Related Issue: None

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Breaking Changes

None.

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Reviewer Notes

The primary implementation is the addition of payload_cached_size to the module metadata cache and updating payload compatibility checks to consume the cached value.

The accompanying RSpec tests verify:

• Msf::Payload.cached_size behavior.

• Payload cached size metadata generation and validation.

• Handling of static and dynamic payloads.

• Cached size override generation for staged payloads.

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Verification Steps

1. Build the project and install dependencies.

2. Apply this patch.

3. Run:

bundle exec rspec spec/lib/msf/core/payload_spec.rb

Expected result:

• 12 examples

• 0 failures

4. Run:

bundle exec rspec spec/lib/msf/util/payload_cached_size_spec.rb

Expected result:

• 16 examples

• 0 failures

5. Verify that payload metadata now includes payload_cached_size.

6. Verify that is_payload_compatible? correctly rejects payloads whose cached size exceeds the available payload space, including dynamically-sized payloads.

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Test Evidence

Test 1

bundle exec rspec spec/lib/msf/core/payload_spec.rb
Finished in 0.64117 seconds (files took 6.53 seconds to load)

12 examples, 0 failures
Coverage report generated for RSpec to coverage.

Line Coverage: 18.54% (2683 / 14471)

Test 2

bundle exec rspec spec/lib/msf/util/payload_cached_size_spec.rb

Finished in 0.468 seconds (files took 5.94 seconds to load)

16 examples, 0 failures
Coverage report generated for RSpec to coverage.

Line Coverage: 16.86% (2238 / 13275)

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Environment

Field	Details
Operating System	Ubuntu 24.04.4 LTS
Ruby Version	Ruby 3.2.x
PostgreSQL	PostgreSQL 16
Target Software/Hardware	Metasploit Framework (master branch)
Docker Image / Vagrant Setup	Not used

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AI Usage Disclosure

ChatGPT was used to assist with drafting the pull request description and improving documentation. The implementation, testing, debugging, and validation of the code were completed by the contributor.

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Pre-Submission Checklist

• No sensitive information (credentials, API keys, IP addresses, or secrets) included

• Tested on the target environment specified above

• Included RSpec tests for library changes

• Read the CONTRIBUTING.md and module acceptance guidelines

• Included a corresponding documentation markdown file (Not applicable — library change only)

[keyanskv]

Hello Maintainers,

I have reviewed the proposed changes in this pull request and believe they are ready for GitHub Actions to run. Could a maintainer please review the changes and approve the pending workflow execution?

Thank you for your time and assistance.