IIS 4.0 FTP servers which have installed a specific post SP5 FTP hotfix are vulnerable to an exploit whereby FTP clients may download. and/or delete files (on the FTP server) that have been specifically marked as 'No Access' (via NTFS file or directory permissions). Web browser FTP clients may be able to view and/or download these files, while specially crafted requests from non-browser based FTP clients may be able to delete these files. This vulnerability only affects IIS 4.0 servers running NT 4.0 SP5 with a specific post SP5 hotfix for an FTP get error as described in <http://support.microsoft.com/support/kb/articles/Q237/9/87.ASP >. Microsoft states there are no negative ramifications to applying this hotfix to SP4 or SP5 hosts who have not installed the previously referenced FTP hotfix. To see if you are vulnerable, check the file version for Ftpsvc.dll. Versions 0718 through 0722 are thought to be vulnerable, although Microsoft documentation is unclear as to whether the...
IIS 4.0 FTP servers which have installed a specific post SP5 FTP hotfix are vulnerable to an exploit whereby FTP clients may download. and/or delete files (on the FTP server) that have been specifically marked as 'No Access' (via NTFS file or directory permissions). Web browser FTP clients may be able to view and/or download these files, while specially crafted requests from non-browser based FTP clients may be able to delete these files. This vulnerability only affects IIS 4.0 servers running NT 4.0 SP5 with a specific post SP5 hotfix for an FTP get error as described in <http://support.microsoft.com/support/kb/articles/Q237/9/87.ASP >. Microsoft states there are no negative ramifications to applying this hotfix to SP4 or SP5 hosts who have not installed the previously referenced FTP hotfix. To see if you are vulnerable, check the file version for Ftpsvc.dll. Versions 0718 through 0722 are thought to be vulnerable, although Microsoft documentation is unclear as to whether the vulnerable versions start with 0718 or 0719. Version 0724 represents the version installed by the latest hotfix. The hotfix designed to correct this problem was not released in time for the upcoming NT 4.0 Service Pack 6. Service Pack 6 contains the "buggy" hotfix and will be vulnerable to this error when it is released. It will be necessary to install the corresponding hotfix after installing Service Pack 6, regardless of whether or not the Service Pack 5 installation was vulnerable.
