Several F-Secure products are affected by archive file scan bypass vulnerabilities: user decompressable, crafted RAR archives cannot be parsed (opened) by Anti-Virus user decompressable, crafted LHA archives cannot be parsed (opened) by Anti-Virus An attacker may create a specially crafted LHA or RAR archive file with manipulated archive file header fields and malicious contents, which then goes through Anti-Virus scanning without interception. The manipulated file header fields basically break the archive file from Anti-Virus point of view, but certain decompression programs are still capable of opening archive for the user, in some cases with errors displayed.