Frisk F-Prot Antivirus allows remote attackers to bypass protection via a ZIP file with a version header greater than 15, which prevents F-Prot from decompressing and analyzing the file.
Multiple interpretation error in F-Prot 3.16c allows remote attackers to bypass virus scanning via a file such as BAT, HTML, and EML with an "MZ" magic byte sequence which is normally associated with EXE, which causes the file to be treated as a safe type that could still be executed as a dangerous file type by applications on the end system, as demonstrated by a "triple headed" program that contains EXE, EML, and HTML content, aka the "magic byte bug."