The decompress function in compress42.c in (1) ncompress 4.2.4 and (2) liblzw allows remote attackers to cause a denial of service (crash), and possibly execute arbitrary code, via crafted data that leads to a buffer underflow.

ncompress 4.2.4 and earlier allows local users to overwrite arbitrary files via a symlink attack on temporary files using (1) zdiff or (2) zcmp, a different vulnerability than CVE-2004-0970.

Stack-based buffer overflow in the comprexx function for ncompress 4.2.4 and earlier, when used in situations that cross security boundaries (such as FTP server), may allow remote attackers to execute arbitrary code via a long filename argument.