Interpretation conflict in ASP.NET in Microsoft .NET Framework 1.0, 1.1, and 2.0 for Windows 2000, XP, Server 2003, and Vista allows remote attackers to access configuration files and obtain sensitive information, and possibly bypass security mechanisms that try to constrain the final substring of a string, via %00 characters, related to use of %00 as a string terminator within POSIX functions but a data character within .NET strings, aka "Null Byte Termination Vulnerability."