A regular expression Denial of Service (DoS) vulnerability in the file lib/ecstatic.js of the ecstatic npm package, before version 2.0.0, allows a remote attacker to overload and crash a server by passing a maliciously crafted string.
https://github.com/jfhbrook/node-ecstatic/commit/71ce93988ead4b561a8592168c72143907189f01