Several vulnerabilities have been discovered in mapserver, a CGI-based web framework to publish spatial data and interactive mapping applications. The Common Vulnerabilities and Exposures project identifies the following problems: Missing input validation on a user supplied map queryfile name can be used by an attacker to check for the existence of a specific file by using the queryfile GET parameter and checking for differences in error messages. A lack of file type verification when parsing a map file can lead to partial disclosure of content from arbitrary files through parser error messages. Due to missing input validation when saving map files under certain conditions it is possible to perform directory traversal attacks and to create arbitrary files. NOTE: Unless the attacker is able to create directories in the image path or there is already a readable directory this doesn't affect installations on Linux as the fopen() syscall will fail in case a sub path is not readable. It was discovered that mapserver is vulnerable to a stack-based buffer overflow when processing certain GET parameters. An attacker can use this to execute arbitrary code on the server via crafted id parameters. An integer overflow leading to a heap-based buffer overflow when processing the Content-Length header of an HTTP request can be used by an attacker to execute arbitrary code via crafted POST requests containing negative Content-Length values. An integer overflow when processing HTTP requests can lead to a heap-based buffer overflow. An attacker can use this to execute arbitrary code either via crafted Content-Length values or large HTTP request. This is partly because of an incomplete fix for CVE-2009-0840.