mandiant / mandiant/capa

Performance and accuracy: filter out functions

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enhancement performance
Dominant language
Python
Stars
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Forks
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Avg merge
11d 11h
Merged PRs (30d)
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Description

Goal: filter out more functions that slow down performance and often only provide FP matches.
Main concern: this could prevent some matches

Initial ideas:
- lightweight library ID, functions with
- many basic blocks
- surrounding functions are library code
- no/few api calls?
- only calls to/from library code (see #989)
- trim functions with too many basic blocks in general

Anecdotally, huge/complex functions are library code or obfuscated and make analysis slow.
Can we heuristically identify them and don't even extract their features, except maybe a new characteristic (complex/un-analyzed function) or just a warning in the results.

Example: https://github.com/mandiant/capa-rules/issues/435 (non public sample) and it would be good to collect more test samples on this.

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First steps

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  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by reviewing the function-extraction behavior described here, the related discussion in #989, and the non-public example referenced from capa-rules #435. Collect additional test samples and evaluate candidate heuristics for complex or library functions, with completion defined by documented trade-offs between performance and missed matches.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
performance, reverse-engineering
Issue type
Feature
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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