lighttpd before 1.4.14 allows attackers to cause a denial of service (crash) via a request to a file whose mtime is 0, which results in a NULL pointer dereference.

lighttpd 1.4.12 and 1.4.13 allows remote attackers to cause a denial of service (cpu and resource consumption) by disconnecting while lighttpd is parsing CRLF sequences, which triggers an infinite loop and file descriptor consumption.