A heap-based read buffer overflow has been found in curl < 7.55.0. In the globbing function that parses the numerical range, there was an omission that made curl read a byte beyond the end of the URL if given a carefully crafted, or just wrongly written, URL. The URL is stored in a heap based buffer, so it could then be made to wrongly read something else instead of crashing. An example of a URL that triggers the flaw would be http://ur%20[0-60000000000000000000. This flaw only affects the curl command line tool, not the libcurl library.