560674e2de
* feat(native): report binary hardening for ELF, PE and Mach-O Documents inspect_binary_hardening and its CLI equivalent, including per-property states, supporting evidence, read budgets, and one report per Mach-O slice. Explains that missing protection imports remain unknown, signature presence does not establish validity, and hardened runtime requires inspect_signature. Adds hardening links throughout the documentation. The supplied diff also removes the advanced CodeQL workflow and configuration, along with snapshot-binding mismatch guidance. * fix(native): validate declared payloads and dynamic tables before hardening rows Run the shared range checks for ELF, read imports from the dynamic tables rather than section metadata, and keep an unresolved symbol count apart from an absent table. Check every Mach-O command before building rows and retain only the offsets the rows need. Make the verifier's readelf output wide, check the emitted format before parsing Mach-O, and place the sources before the libraries in the link. * fix(native): share Mach-O segment admission with hardening reads A segment with a section count its cmdsize cannot hold passed the hardening reader and could enable restrict_segment. Move the size, section count and file range checks to a shared admission that readMachoImage and the hardening reader both use, and pin the ELF load-size case with a regression test. * fix(hardening): reject Mach-O section payloads past the slice and empty ELF interpreters Segment admission never checked each section's payload range, so a file-backed section past the slice still produced rows. Decode sections with the section header owner and mark the slice malformed when a payload leaves it; zero-fill and empty sections own no file bytes and are exempt. admitInterp accepted a NUL first byte in a longer extent, which counted an empty interpreter as PIE evidence. It now requires a nonempty path. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01KuWHGvzJkrhCqjtEHUwqyH * fix(native): read CFG instrumentation from decoded GuardFlags Use the IMAGE_GUARD_CF_INSTRUMENTED flag that guardFlagRecord already decodes instead of masking the raw GuardFlags word a second time. * fix(native): reject ELF table spans a second PT_LOAD remaps The hardening reader mapped DT_STRTAB, DT_SYMTAB and hash tables through the one PT_LOAD containing the table's first address. A second PT_LOAD starting inside the table could map the rest of it from other file bytes and the reader still reported parsed import evidence. Cap each mapping at the next PT_LOAD that starts inside it, reject a requested range that crosses that boundary, and stop hash reads at the same limit, matching the conflicting-mapping refusal in readElfSymbols. * fix(native): dedupe ELF note tables only on shared boundaries The hardening reader dropped any note table whose bytes another table already covered. A covering SHT_NOTE can hold a non-GNU note whose descriptor is itself a complete GNU property note, while PT_NOTE names that inner note directly. Walking only the outer stream missed the GNU marker and reported CET disabled. Drop an alias only when it starts and ends on boundaries of admitted tables, which are note boundaries of the walked streams. Any other covered alias leaves the feature rows unknown, as a partial overlap already does. * fix(native): admit every Mach-O symbol record after a canary match The Mach-O stack protector scan returned as soon as it found an undefined ___stack_chk_fail, so a later undefined symbol whose n_strx lay outside the string table was never checked. The same damaged table parsed or failed as malformed depending only on record order. Keep the match and finish the bounded record walk. Records after the match are only checked against the string table bounds, so their names are not read or charged to the scan budget. The ELF reader already admits its whole symbol table before matching names. * fix(native): accept ELF load aliases with the same file translation The hardening reader treated every PT_LOAD that starts inside a table, or that also contains the table's address, as a conflicting mapping. A load with the same address-to-file translation names the same file bytes, so tables it overlaps still have one interpretation, and the canonical ElfLoadMap already merges such spans. Treat equivalent loads as one interpretation. A load with a different translation, or the zero-filled tail of an equivalent load, still ends the usable range, so a remapped table is still rejected. * fix(native): keep same-span ELF note tables with different alignments unknown A section and a program header that share endpoints were treated as one note stream even when their effective note alignments differed. Walking the same bytes at 4 and 8 can frame different notes, so dropping the second table could hide a GNU property word and report CET or BTI as disabled. Require matching effective alignment at both endpoints, and no alignment change inside the covered span, before treating a table as an alias. Otherwise mark the feature rows unknown. The fixture's .note.gnu.property section now declares the class's note alignment, as toolchains emit it. * refactor(native): read LC_SYMTAB through the shared fixed-word decoder Move the Mach-O fixed uint32 command layouts out of MachoCommandNames into domain/apple/machoLoadCommands so there is one owner of those offsets. MachoCommandNames and the hardening reader now both decode through it; the hardening reader keeps its own bounds and import policy. * fix(native): skip Mach-O common definitions in canary imports A common definition sets N_UNDF|N_EXT like an import but stores its allocation size in n_value. An object holding only `int __stack_chk_fail;` therefore reported stack_protector: enabled. Require a zero n_value before an undefined external counts as an import, for both nlist widths. * refactor(native): read linkedit data commands through the shared fixed-word decoder readMachoLinkeditDataCommand reproduced the dataoff/datasize offsets that FIXED_WORD_FIELDS already owns. Take the command and decode through decodeMachoFixedWordFields, as readMachoSymtabCommand does, keeping the truncation and endianness behavior. * fix(native): skip empty SHT_NOTE sections in ELF hardening A zero-sized SHT_NOTE owns no bytes, so the section directory marks it not file-backed and the hardening reader rejected the whole image as malformed, while readElfImage accepted the same bytes. Skip empty note sections before the file-backing check; they have nothing to walk. * fix(scripts): run hardening verifier commands through the shared owner The binary hardening verifier started its probes and compiler drivers with raw spawnSync, which bypassed the src/process/ supervision that AGENTS.md requires. Every launch now goes through createVerifierCommands, and the temporary root is removed only after the owner closes cleanly. * fix(scripts): clean up hardening verifier commands on Ctrl-C SIGINT or SIGTERM ended Node before withVerifierCleanup ran, so detached compiler trees and the temporary root could outlive the verifier. The verifier now turns those signals into an abort that every owned command receives, so cleanup closes the owner and removes the root before exit. * fix(scripts): fail the hardening verifier when a signal lands outside a command Only the owned commands read the interruption signal, so a SIGINT or SIGTERM during the final cleanup or between commands was recorded and then dropped, and the verifier exited 0. After cleanup settles, the verifier now throws the interruption reason. A failure the operation or its cleanup already raised still leaves first and is not replaced. * fix(native): fail Mach-O slices with a malformed encryption command The hardening reader turned every malformed status from the shared encryption reader into an unknown `encrypted` row, so a short LC_ENCRYPTION_INFO_64 or an encrypted range past the slice still left the slice parsed with a full report. Only two conflicting encryption commands stay an unknown row now. Any other encryption defect fails the slice like other structural command failures. * fix(native): ignore STB_LOCAL undefined ELF symbols as imports A local undefined __stack_chk_fail or __memcpy_chk is never resolved against another object, so it does not establish an external import. Skip STB_LOCAL bindings when reading protector signs, and give the fixture's positive symbols STB_GLOBAL binding. --------- Co-authored-by: Matt Van Horn <455140+mvanhorn@users.noreply.github.com> Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
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REA: Reverse Engineer Anything
One MCP for reverse engineering across binaries, applications, and runtime behavior.
See a feature you like. Understand how it works, down to the binary level.
Quick start · How REA works · What you can analyze · Showcases · Build RL environments · FAQ · Documentation
npx rea-agents setup
Important
Get REA from morluto/rea, rea.tools, or the rea-agents npm package. Follow the installation and release links from these official sources. A similar repository name or copied README does not establish that a download is official.
See a feature in an app that you want in your own product? Ask your agent to investigate it with REA. It can inspect the app without its source code, explain how the feature works, show the evidence, and build a version for your project.
REA connects your agent to tools for inspecting native binaries, JavaScript and Electron apps, .NET assemblies, and websites. You can also use the same tools from your terminal. Analysis runs locally, and results include the evidence and limitations behind each conclusion.
Setup registers REA with your agent and installs matching workflow instructions. Native analysis can use an existing Hopper, Ghidra, IDA or Kuna installation; setup can optionally install Hopper with approval. Static JavaScript analysis needs no native analysis engine.
Visit the REA website for setup instructions, illustrated guides, and real case studies.
Quick start
On Linux, Ghidra, JADX, firmware tool launches and static JavaScript/Electron
analysis require a procps-compatible ps on REA's PATH for process ownership
checks. Recovery steps are in docs/installation.md under
"Linux owned-process prerequisite".
Set up your agent
With Node.js and npm installed, run:
npx rea-agents setup
Choose your agents, review the proposed changes, and approve them. Setup adds REA's MCP server and matching workflow instructions, with backups of existing configuration. Restart your agent afterward. Setup records the selected runtime and REA entry script directly. If acquired through a package runner, keep its cache entry available. Run package acquisition from a trusted directory outside the target project. Installation and recovery details are in the setup guide below.
Setup supports Claude Code, Codex, Cursor, Gemini CLI, Grok Build and other agents. See installation and setup for provider configuration and manual MCP registration and Claude Code/Codex plugin installation.
MCP uses compact input schemas by default to reduce context overhead. Set
REA_MCP_INPUT_SCHEMA_PROFILE=full in your MCP registration when you need the
complete advertised field guidance and nested validation details. Both profiles
keep the full tool set and canonical server validation. See
"Compact input schema profile" in the MCP contracts guide.
Complete output schemas are advertised by default. If your client caps the
complete tools/list frame, set REA_MCP_OUTPUT_SCHEMA_PROFILE=compact to
bound each advertised output schema, or off to omit output schemas entirely.
Both settings keep canonical server-side validation and complete structured
results. See "Output schemas" in the MCP contracts guide.
Ask your agent
Understand how search works in the Notes app, show me the evidence, and build a
similar feature for my project.
Replace Notes with your target app and the feature you want to understand.
Use the terminal
Inspect an extracted JavaScript/Electron app directory or ASAR:
npx -y rea-agents@latest analyze-javascript-application /absolute/path/to/app --json
The result includes modules, imports, Electron boundaries and their evidence.
Replace the path with your target, such as "D:/apps/example" on Windows.
To install the rea command for regular use:
npm install --global rea-agents
rea --help
For native analysis, configure a provider first. See the CLI and Evidence guide for native commands, provider selection, snapshots and scripting.
Update REA
REA changes quickly, and new releases include frequent bug fixes. Keep your installation up to date.
For a CLI installed with npm install --global or bun add --global:
rea update
rea --update is an alias for this verified workflow and accepts the same global
output flags. Use rea update when combining it with other command controls.
Updater commands retain at most 4 MiB of stdout and stderr combined. Oversized metadata replies are rejected after the command exits; verbose installs continue with bounded diagnostics. Human progress output respects terminal backpressure and waits for submitted writes to finish.
Bun global updates require Bun 1.2.17 or later. With an older Bun release,
upgrade Bun manually before running rea update.
To refresh your agent registrations and skill, run the setup command printed by the update.
If you use npx, update your agent setup with:
npx rea-agents@latest setup
Review the setup changes and restart your agent. For one-off CLI commands,
use npx rea-agents@latest followed by the command. With Bun, use
bunx rea-agents@latest in place of npx rea-agents@latest.
How REA works
Your agent calls REA through MCP to inspect the target and trace relevant code. REA returns findings with their evidence. The agent uses them to ask follow-up questions, explain the behavior, or write and test an implementation. CLI commands use the same workflows.
What you can analyze
REA requires Node.js 22.x (>=22.23.4), 24.x (>=24.22.1), or 26.12.1+, plus npm. Additional tools and host support depend on the target:
| Target | What REA returns | Requirements and guide |
|---|---|---|
| Desktop installations | Runtime candidates, supporting files, component markers and next probes | Built-in bounded directory/header inspection; desktop applications |
| Native binaries | Pseudocode, assembly, strings, symbols, calls and references | Hopper, Ghidra, IDA or Kuna; native analysis |
| Offline ELF layout | Sections, segments, original symbols/relocations and static mitigation candidates | Caller-supplied pwntools on Linux x64; binary diagnostics |
| Go binaries | Embedded compiler version, modules, replacements and build settings | Built-in static ELF/PE/thin Mach-O inspection; no Go installation required |
| GPU code objects | CUDA/HIP targets, selected kernel parameters and resources, retained PTX text | Built-in static ELF/PE/fatbin/CUBIN/PTX inspection; GPU code objects |
| Model artifacts | GGUF / safetensors metadata, tensor declarations and derived totals | Built-in header inspection; optional full-file hash; model files |
| IL2CPP metadata | Unity global-metadata.dat assembly images, type and method names and index ranges | Built-in static decoding of versions 24, 27, 29, 31 and 39; no Unity required |
| Godot PCK | Archive inventory and extraction, original header/directory facts and selected content identities | Built-in static formats 2, 3 and 4; no Godot required |
| Rust binaries | Embedded cargo-auditable crate names, versions, sources and dependency edges | Built-in static ELF/PE/thin Mach-O inspection; Rust binaries |
| PE certificates | Authenticode WIN_CERTIFICATE entries and PKCS#7 signer/X.509 identity fields | Built-in static PE inspection; PE certificates |
| PE imports | Import and delay-load DLL names, ordinals, IAT RVAs and pefile import hash | Built-in static PE inspection; PE imports |
| ELF notes | PT_NOTE/SHT_NOTE owners, types, GNU build-id and ABI-tag fields | Built-in static ELF inspection; ELF notes |
| Binary hardening | PIE, NX, RELRO, CFG and related header flags for ELF, PE and Mach-O | Built-in static header inspection; binary hardening |
| Apple IPS crashes | .ips metadata, threads, images, registers and documented crash classes | Built-in static JSON inspection; Apple IPS |
| Linux kernel modules | .modinfo keys, __versions CRCs, this_module presence, and signature trailer | Built-in static ELF inspection; kernel modules |
| Erlang BEAM | IFF chunks, atoms, exports, imports, lambdas and the Code header | Built-in static BEAM inspection; Erlang BEAM |
| WASM artifact | Validation, sections, exact import/export WAT forms and decoded WAT | Caller-supplied WABT 1.0.42; inspect_wasm_artifact |
| EVM bytecode | Dispatch selectors, byte offsets, inferred arguments and mutability | Local raw/hex carrier on Linux x64; offline EVM guide |
| SQLite databases | Tables, columns, indexes, views, triggers and selected ordinary-table rows | Local database/WAL snapshot; Node.js 24.x >=24.15 or 26+ with native SQLite limits |
| Recorded Linux crashes | Raw notes, every recorded thread's registers/signals and optional mapping candidates | Caller-supplied pwntools on Linux x64; optional GDB/pwndbg; recorded crashes |
| JavaScript / Electron | Modules, imports, source maps, routes, IPC and native add-on relationships | Node.js and npm; Linux: procps-compatible ps; application analysis |
| Websites | Page structure, scripts, network observations and requested screenshots | A Chrome-family browser; browser analysis |
| Saved network captures | Requests, responses, exposed payloads and source locations | HAR or Fiddler Everywhere SAZ; mitmdump on Linux for native mitmproxy; capture guide |
| .NET assemblies | Metadata, CIL instructions, declared native dependencies and build comparisons | None (static only); managed-code guide |
| Android APKs | Manifest declarations, classes, decompiled methods and references | Headless JADX and a full JDK on Linux/macOS/Windows x64; Android guide |
| APK signatures | v1/v2/v3/v3.1 signers, certificate fingerprints, key rotation and digest self-consistency | None (static only); inspect_apk_signature |
| Android devices | Devices, packages, processes, logs, dumps, screen captures, and APK/file transfers | Caller-supplied adb (emulator or hardware); ADB guide |
| JEB projects | Engine-backed project units, artifact digests and type/method pseudo-code | A caller-started JEB client serving MCP, selected with REA_JEB_MCP_URL; JEB guide |
| Android resources | Decoded manifest, string tables, locales and version facts | Caller-supplied Apktool launcher; resource guide |
| Flutter apps | Dart snapshot hash, per-ABI library digests and engine build provenance | None (static APK parsing); Flutter guide |
| Firmware | Regions, extraction results and native-analysis handoffs | Binwalk / Unblob on Linux; firmware guide |
| Recorded packets | Selected fields, repeated values, filters and decode-as rules | Linux: TShark 4.x + prlimit; capture guide |
| Packet summaries | Endpoints, DNS, TLS SNI, protocol distribution and HTTP requests | Caller-supplied tshark and capinfos (Linux-verified); pcap guide |
| Recorded logic signals | Decoder annotations, sample ranges and diagnostics | Linux: sigrok-cli 0.7.2 + prlimit; signal recordings |
| Packages and resources | File inventories, digests, plists, Apple bundle anatomy and extracted resources | Artifact and JavaScript guide, Apple applications |
| Process behavior | Terminal output, interactions, exit and filesystem observations, and run comparisons | Linux/macOS with a native PTY; process capture |
| PyInstaller executables | CArchive members, Python version, entry scripts and extracted bytecode | None (static only); Python packaged applications |
Static JavaScript and .NET inspection read the supplied files without running the application. Runtime capture runs or interacts with the selected target using your user permissions; each runtime guide describes its effects.
For offline native-binary inspection, REA also supports caller-supplied GNU objdump and Rizin. See the reverse-engineering tools guide for provider setup, CLI commands, and Evidence limitations. REA does not install or update either provider.
Native formats and host support vary by provider. See
Hopper and Ghidra setup, the
IDA guide (including an optional native MCP bridge), the
Kuna decompiler guide, and
experimental Windows Ghidra support.
Ghidra also supports 16-bit DOS analysis.
For large binaries, raise the provider's startup deadline with
REA_GHIDRA_STARTUP_TIMEOUT_MS or REA_HOPPER_STARTUP_TIMEOUT_MS.
For provider selection, see the CLI guide.
Check release availability
for features added since the latest npm release.
Showcases
DX-Ball: reconstruct a sound-pan calculation
Follow a sound call into its position-to-pan helper, inspect the instructions, and turn incomplete pseudocode into C. The reconstruction passes 3,205 original-x86 cases and reproduces all 63 compiled function bytes.
Read the case study · Reconstruction repository
Notion: trace the Electron clipboard bridge
Find the renderer's clipboard API, follow it through preload and IPC into the main process, and inspect the rich clipboard format.
TH04: recover a DOS bullet-ring calculation
Inspect the original PC-98 game's 16-bit instructions, recover the fixed and aimed angle calculations, and compare the reconstructed C++ with the historical compiler output.
Read the case study · Reconstruction repository
Build RL environments with REA
Record a web app session, turn its API into tools, and export an environment an AI agent can use. Run it with AgentEnv, then add tasks and reward checks for RL training or evaluation.
Read the guide · Watch the video
If you've used REA on something interesting, we'd love to see it. Share your case in an issue or a pull request, including the target, your question, how REA helped, and what you found.
Build RL environments
Give an AI agent a local environment to practice tasks such as finding an issue or creating a folder, without running the original app. Use it for reinforcement learning (RL) or to test how well an agent completes tasks.
REA turns recorded API requests and responses into tools the agent can call. The environment uses the recorded data and supports changes only when the recording confirms their effects.
With REA set up in your agent, replace the example URL and folder tasks below with your own:
Use REA to build an RL environment from my test web app at
http://127.0.0.1:3000.
Cover listing, creating, renaming, and deleting folders. You may create and
remove test folders. Leave existing data unchanged.
Save it in a folder named my-env. Check which operations work and tell me
how to run it.
Use the command line instead
Use these commands if you already have a file containing the app’s recorded browser requests and responses. Running the result also requires AgentEnv and Docker.
rea environment-build ./session.har ./my-env --name my-env --json
agent-env run ./my-env
REA exports a runnable environment with a basic test to check that it starts and responds. Use it with your RL framework to define task goals, add reward checks, and run training.
Build an environment · Environment reference · Watch the demo on X
FAQ
Which agents can use REA?
Any agent that supports local MCP servers. Setup configures the supported agents; other clients can use manual MCP registration.
Do I need a native analysis engine?
Deep native analysis uses Hopper, Ghidra, IDA or Kuna, depending on the target and operation. Static JavaScript and .NET inspection work without a native analysis engine. Setup can install Hopper after approval; Ghidra, IDA and Kuna use your existing installations. See provider setup for the options and their supported targets.
Do I need to start Hopper first?
REA starts Hopper when an operation needs it. On macOS, a first-run dialog may ask you to choose demo mode or activate your license. Complete that prompt in the same user session before your first CLI/MCP operation or unattended job. Open Hopper manually if needed. See Hopper startup and troubleshooting.
What does installing the skill from skills.sh do?
The skill supplies investigation instructions for your agent. Use npx rea-agents setup
to register REA's MCP server and install the matching instructions, then restart
your agent. See skill-only installation.
What code does REA return?
Native analysis returns pseudocode and assembly. JavaScript/Electron analysis recovers modules and their relationships. Your agent uses these findings to write and test an implementation; the showcases give worked examples.
Does REA upload my app?
REA analyzes targets locally. Your agent receives the tool results, and its model provider has its own data policy.
What should I do if I hit a bug?
Update first; a recent release may already fix it.
For a CLI installed with npm install --global or bun add --global:
rea update
For agent setup through npx:
npx rea-agents@latest setup
If you're using an agent, complete the setup refresh and restart it. Retry the same task. If the problem persists, open an issue with your REA version, target type, steps to reproduce and error output.
Documentation
Start with the website's worked guides. For exact options, prerequisites and result contracts:
- Installation and setup: agent registration, provider configuration, updates and uninstall.
- Readiness and troubleshooting: diagnose one agent or analysis engine.
- CLI and Evidence: commands, provider selection, snapshots, import/export and exit statuses.
- MCP contracts and agent prompts: tool results, sessions and guided investigations.
- Tool catalog: generated inventory of tools, providers and CLI commands.
- Roadmap: planned work and capability trackers.
Report vulnerabilities through SECURITY.md.
Star history
🎉 400,000 GitHub stars — thank you!
Thanks to everyone using REA, reporting bugs, requesting features, testing builds, and contributing fixes.
Disclaimer
See DISCLAIMER.md for responsible-use guidance.
The project's position on illegal or unauthorized use covers all REA versions, distribution channels, and platforms; each copy retains its applicable licenses.
REA is for lawful research, education, interoperability, software preservation, and analysis of software you own or are authorized to examine.
Contributing
We'd love your help with REA! Open an issue to report a bug or suggest a feature, or send a pull request to improve the code or docs.
See CONTRIBUTING.md for development setup and checks, testing for verification lanes, and the architecture map for selected layers and dependency paths.
License
REA-authored code is licensed under MIT. Third-party material retains its own licenses and copyright notices; see Third-party notices for the dependency inventory, preserved license texts, and external-tool terms.
You must legally obtain and be authorized to use commercial tools, including IDA Pro / Hex-Rays decompilers, Hopper, and JEB, under their applicable licenses. REA grants no tool license, key, or activation entitlement. Trials and demos remain subject to vendor terms, including user, feature, automation, and output sharing restrictions. Cracked copies, stolen keys, unauthorized key sharing, and bypassing license restrictions are not authorized. This guidance does not amend MIT or third-party licenses.