A path traversal vulnerability exists in httpdasm version 0.92, a lightweight Windows HTTP server, that allows unauthenticated attackers to read arbitrary files on the host system. By sending a specially crafted GET request containing a sequence of URL-encoded backslashes and directory traversal patterns, an attacker can escape the web root and access sensitive files outside of the intended directory.
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.