Packer / packing
Definition
A technique in which the original malware code is compressed or encrypted and wrapped in a stub loader that decompresses or decrypts it at runtime. Packed binaries frustrate static analysis because the real payload is not visible in the file bytes; only the stub is available to the disassembler until the sample is executed or the packer is reversed.
Related terms
- Cryptographic hash
- A fixed-length digest produced from a file's bytes by an algorithm such as MD5 (128-bit), SHA-1 (160-bit), or SHA-256 (256-bit). Identical files...
- Disassembly
- The process of converting raw binary machine code back into human-readable assembly language instructions. Disassembly is always achievable from a binary, unlike...
- Import Address Table (IAT)
- A section of the PE header that lists every external DLL and the functions the executable calls from each. A malware sample's...
- Indicator of Compromise (IoC)
- An observable artefact that suggests a system has been involved in a malicious event. Static analysis produces file-based IoCs: cryptographic hashes, embedded...
- Portable Executable (PE)
- The binary file format used by Windows executables (.exe), dynamic-link libraries (.dll), and drivers (.sys). The PE header contains a structured metadata...
Explained in
- Static Malware AnalysisA technique in which the original malware code is compressed or encrypted and wrapped in a stub loader that decompresses or decrypts it at runtime. Packed bina...