LZEXE

Revision as of 17:35, 1 April 2022

LZEXE is an executable compression utility, developed by Fabrice Bellard. It compresses DOS .EXE files.

Identification

LZEXE-compressed files normally have ASCII "LZ09" or "LZ91" at offset 28.

As with most compressed executable formats, more-robust identification is possible, by looking for the characteristic decompression code.

Software

Compression software

• LZEXE
  • v0.90 (1989-10-30)
  • v0.91 (1990-01-02)
  • v0.91e (1990-10-15). Alternate link: [1]
• "LZEXE v1.00a" by IS2 France Diffusion. Seems to be functionally identical to LZEXE 0.91.

Static decompression software

• UNLZEXE - A widely-distributed open source utility that does static decompression of LZEXE-compressed executables. Originally by Mitugu Kurizono (Kou). Versions "0.6" and above include patches by other authors, and might be unofficial.
  • v0.2 (1990-03-29)
  • v0.4 (1990-05-12)
  • v0.5 (1990-05-17)
  • v0.7
  • v0.8
  • https://github.com/mywave82/unlzexe - Modernized source code
• mz-explode
• Deark (with -m lzexe option)
• Rizzle

Dynamic decompression software

• UNP - An example of a dynamic decompression utility for DOS

Protectors

(utilities that modify a compressed file to make it more difficult to identify and/or decompress)

• ANTI-UNLZEXE
• LZALT v0.03 by Codon Software
• LZEALT v1.04 by De Trans Software

Links

• LZEXE home page
• Reversing LZ91 from Commander Keen