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: CVE-2009-0843 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. CVE-2009-0842 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. CVE-2009-0841 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. CVE-2009-0839 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. CVE-2009-0840 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. CVE-2009-2281 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. For the oldstable distribution , this problem has been fixed in version 4.10.0-5.1+etch4. For the stable distribution , this problem has been fixed in version 5.0.3-3+lenny4. For the testing distribution , this problem has been fixed in version 5.4.2-1. For the unstable distribution , this problem has been fixed in version 5.4.2-1. We recommend that you upgrade your mapserver packages.