We are thankful to Jacob Thompson - Mandiant Advantage Labs for reporting this issue. We already prohibited extracting contents of such malformed archives in WinRAR 6.01. It is done to prevent possible attacks with inclusion of ZIP archive into the signature body.
Authenticity information may be added for additional security and RAR will store information on the last update and name of the archive. Even physically damaged archives may be repaired and an archive may be locked to prevent further changes. RAR offers a number of service functions, such as setting a password, adding archive and file comments.RAR offers the ability to create a multi-volume archive as SFX.RAR offers the ability to create and change SFX archives using default and external SFX modules.RAR provides functionality for creating a 'solid' archive, which can raise the compression ratio by 10% - 50% over more common methods, particularly when packing large numbers of small files.RAR offers an optional compression algorithm highly optimized for multimedia data.It allows higher compression ratios than other PC archiving tools, especially on executable files, object libraries, large text files, etc. RAR introduces an original compression algorithm.The archive is usually a regular file, which name has a '.rar' suffix.
