# Untangle: a browser rebuild from REA and Ghidra evidence

> An author-documented REA/Ghidra investigation of the shipped Untangle Windows binary produces a single-page playable rebuild and a claim-by-claim grading receipt. The report separates frozen findings, a later source-code answer key and a prior-knowledge audit.

- Type: Case study
- Targets: Binary · Game
- Category: Community REA investigations
- Relationship: Author-reported mixed workflow
- Sources reviewed: 2026-11-01
- Added to the catalog: 2026-11-01
- Original resource: <https://github.com/az9713/untangle-rebuild>
- Primary source: <https://github.com/az9713/untangle-rebuild/blob/6e9925105247268befeb6faed69025dfce4778fc/README.md>
- Catalog page: <https://awesomerea.org/resources/untangle-rea-evidence-rebuild-case/>
- Record JSON: <https://awesomerea.org/resources/untangle-rea-evidence-rebuild-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/untangle-rea-evidence-rebuild-case/index.md)

## Requirements & limits

- **Prerequisites:** The recorded run uses REA 6.3.0, Ghidra 12.1.4 and Windows 11 against puzzles version 20260923.616da16; the rebuild is available as a browser page.
- **Testing evidence:** The reported 52/54 correct claims and L3 seed fidelity are the author's grading results; ten names absent from REA output indicate possible prior-knowledge contamination.
- **Limits:** The 72 MB evidence export is omitted; its hash is retained. The README documents a pre-publication history rewrite and maps old commit hashes to new ones.
- **License:** Original puzzle binary and source retain Simon Tatham and contributors' MIT license.

## Primary sources

1. <https://github.com/az9713/untangle-rebuild/blob/6e9925105247268befeb6faed69025dfce4778fc/README.md>
2. <https://az9713.github.io/untangle-rebuild/receipt/rebuild-receipt.html>
3. <https://az9713.github.io/untangle-rebuild/rebuild/index.html>

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## About this entry

The description was reviewed against primary sources.
Original editorial content: MIT. Linked projects, papers and assets retain their own rights and licenses.