Buffer overflow in the "Add to archive" command in WinRAR 3.51 allows user-assisted attackers to cause a denial of service (crash) and possibly execute arbitrary code by tricking the user into adding a file whose filename contains a non-default code page and non-ANSI characters, as demonstrated using a Chinese filename, possibly due to buffer expansion when using the WideCharToMultiByte API. NOTE: it is not clear whether this problem can be exploited for code execution. If not, then perhaps the user-assisted nature of the attack should exclude the issue from inclusion in CVE.