Memory leak in the httprequestparse function in request.c in lighttpd before 1.4.20 allows remote attackers to cause a denial of service (memory consumption) via a large number of requests with duplicate request headers.

lighttpd 1.4.18, and possibly other versions before 1.5.0, does not properly calculate the size of a file descriptor array, which allows remote attackers to cause a denial of service (crash) via a large number of connections, which triggers an out-of-bounds access.