{"id":2887,"library":"capstone","title":"Capstone Disassembly Engine","description":"Capstone is a lightweight, multi-platform, and multi-architecture disassembly framework. It provides robust Python bindings, allowing developers to programmatically disassemble machine code for various architectures like X86, ARM, Mips, and PowerPC. Widely used in binary analysis and reverse engineering, Capstone aims to be a comprehensive disassembly engine for the security community. The library is actively maintained, with the current stable version being 5.0.7, and receives regular updates including new architecture support and bug fixes.","status":"active","version":"5.0.7","language":"en","source_language":"en","source_url":"https://github.com/capstone-engine/capstone","tags":["disassembly","reverse engineering","binary analysis","security"],"install":[{"cmd":"pip install capstone","lang":"bash","label":"Install via pip"}],"dependencies":[{"reason":"Requires Python 3.8 or newer for the current version.","package":"python","optional":false},{"reason":"The Python package bundles the native C core; typically no separate installation is required unless inhibiting the bundled build with LIBCAPSTONE_PATH.","package":"libcapstone","optional":true}],"imports":[{"note":"While 'import *' works, it's generally discouraged in larger projects to avoid name collisions and improve readability. Explicitly import required symbols.","wrong":"from capstone import *","symbol":"Cs","correct":"from capstone import Cs, CS_ARCH_X86, CS_MODE_64"}],"quickstart":{"code":"from capstone import Cs, CS_ARCH_X86, CS_MODE_64\n\n# X86 64-bit code to disassemble\nCODE = b\"\\x55\\x48\\x8b\\x05\\xb8\\x13\\x00\\x00\\x48\\x8b\\x01\\x49\\x8b\\x40\\x10\\x48\\x8d\\x34\\x24\"\n\n# Initialize Capstone for X86 64-bit architecture\nmd = Cs(CS_ARCH_X86, CS_MODE_64)\n\n# Disassemble the code\nprint(\"Disassembling X86 64-bit code:\")\nfor i in md.disasm(CODE, 0x1000):\n    print(\"0x%x:\\t%s\\t%s\" % (i.address, i.mnemonic, i.op_str))\n\n# Example with a different architecture (ARM)\nfrom capstone import CS_ARCH_ARM, CS_MODE_ARM\nARM_CODE = b\"\\x04\\xe0\\x2d\\xe5\\x00\\x00\\x00\\x00\"\nmd_arm = Cs(CS_ARCH_ARM, CS_MODE_ARM)\n\nprint(\"\\nDisassembling ARM code:\")\nfor i in md_arm.disasm(ARM_CODE, 0x1000):\n    print(\"0x%x:\\t%s\\t%s\" % (i.address, i.mnemonic, i.op_str))","lang":"python","description":"This quickstart demonstrates how to initialize the Capstone engine for different architectures (X86 64-bit and ARM) and then disassemble a byte string, printing the address, mnemonic, and operand string for each instruction."},"warnings":[{"fix":"Always consult the official release notes and upgrade guides for the specific versions you are migrating between. Re-test your code thoroughly after major version upgrades.","message":"Capstone undergoes significant changes between major versions (e.g., 3.0, 4.0, 5.0), introducing new features, architectures, and sometimes API modifications. For instance, version 3.0.5-rc2 had API version bumps and new `cs_option()` modes. The RISC-V module, in particular, saw enormous changes in a recent update. Users should review release notes and migration guides when upgrading across major versions.","severity":"breaking","affected_versions":"All major version upgrades (e.g., 3.x to 4.x, 4.x to 5.x)"},{"fix":"If you intend to use a pre-existing `libcapstone` installation, set the environment variable `LIBCAPSTONE_PATH` (e.g., `export LIBCAPSTONE_PATH=/path/to/your/libcapstone`) before running `pip install capstone`.","message":"When installing via `pip`, the `capstone` Python package automatically builds and includes its own native C core library. If you have a system-installed `libcapstone` and wish to use it instead, you must set the `LIBCAPSTONE_PATH` environment variable before installation to inhibit the bundled core build. Failure to do so will result in two copies of the library, potentially leading to confusion or unexpected behavior.","severity":"gotcha","affected_versions":"All versions where a system `libcapstone` might conflict with the pip-installed package."},{"fix":"Ensure your code only accesses relevant data fields for the current instruction and mode. If you rely on `skipdata` and `detail` modes, adapt your error handling or data access logic to account for explicit error raising.","message":"In Capstone versions prior to 3.0.5-rc2, accessing irrelevant data fields when `skipdata` and `detail` modes were enabled might have silently returned default values. Since 3.0.5-rc2, the Python binding explicitly raises an error in such cases. This change ensures stricter error handling but can break older code relying on the previous, more lenient behavior.","severity":"breaking","affected_versions":"Prior to 3.0.5-rc2 (leniency) to 3.0.5-rc2 and newer (strict error)."},{"fix":"Prefer explicit imports, e.g., `from capstone import Cs, CS_ARCH_X86, CS_MODE_64`, to clearly identify where symbols originate and avoid potential conflicts.","message":"Using `from capstone import *` is convenient for quick scripts but can lead to name collisions with other modules or variables in larger projects. This makes code less explicit and harder to debug.","severity":"gotcha","affected_versions":"All versions (general Python best practice)."}],"env_vars":null,"last_verified":"2026-04-11T00:00:00.000Z","next_check":"2026-07-10T00:00:00.000Z"}