The webdav_mount function in webdav_vfsops.c in the WebDAV kernel extension (aka webdav_fs.kext) for Mac OS X 10.6 allows local users to cause a denial of service (panic) via a mount request with a large integer in the pa_socket_namelen field.
The Mac OS X WebDAV kernel extension is vulnerable to a denial of service issue that allows a local unprivileged user to trigger a kernel panic due to a memory overallocation.