ClamAV
A GPL virus scanner featuring:
- command-line scanner
- fast, multi-threaded daemon
- database updater with support for digital signatures
- virus scanner C library
- on-access scanning (Linux)
- detection of over 20000 viruses, worms and trojans
- built-in support for RAR (2.0), Zip, Gzip, Bzip2, Tar, MS OLE2, MS Cabinet files, MS CHM (Compressed HTML), MS SZDD
- support for built-in support Portable Executable files compressed with UPX, FSG, and Petite
