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.
The connectionstatemachine function (connections.c) in lighttpd 1.4.19 and earlier, and 1.5.x before 1.5.0, allows remote attackers to cause a denial of service (active SSL connection loss) by triggering an SSL error, such as disconnecting before a download has finished, which causes all active SSL connections to be lost.