Directory traversal vulnerability in a third-party compression library (UNACEV2.DLL), as used in avast! Antivirus Home/Professional Edition 4.6.665 and Server Edition 4.6.460, allows remote attackers to write arbitrary files via an ACE archive containing filenames with (1) .. or (2) absolute pathnames.

Buffer overflow in the Aavmker4 device driver in Avast! Antivirus 4.6 and possibly other versions allows local users to cause a denial of service (system crash) and possibly execute arbitrary code via certain signals combined with crafted input.

Unknown vulnerability in ALWIL avast! antivirus 4 (4.6.6230) and earlier, when running on Windows NT 4.0, does not properly detect certain viruses.